Novel Pentapeptide GLP‐1 (32–36) Amide Inhibits β‐Cell Apoptosis In Vitro and Improves Glucose Disposal in Streptozotocin‐Induced Diabetic Mice

We proposed that a pentapeptide, LVKGR amide, GLP‐1 (32–36) amide, derived from the gluco‐incretin hormone, glucagon‐like peptide‐1 (GLP‐1), might possess favorable actions against diabetes. Therefore, GLP‐1 (32–36) amide was synthesized and the effects of it were examined in INS‐1 cell and streptozotocin‐induced diabetic mice model. To determine the protective effects of GLP‐1 (32–36) amide on INS‐1 cell viability and apoptosis, cells were exposed to 1 μm streptozotocin (STZ) and GLP‐1 (32–36) amide for 24 h. Results showed that GLP‐1 (32–36) amide treatment decreased apoptosis rate and significantly retained cell viability compared with saline‐treated controls. Then, GLP‐1 (32–36) amide was administered intraperitoneally to streptozotocin‐induced diabetic mice with normal mice used as control. Body weight, energy intake, plasma glucose, and histopathology of the pancreas were assessed. Results showed that GLP‐1 (32–36) amide protected β‐cell viability and apoptosis against STZ‐induced toxicity, inhibited weight gain, and relieved symptoms of polydipsia. Moreover, GLP‐1 pentapeptide‐treated mice showed a slight trend toward reduced glucose excursions in intraperitoneal glucose tolerance test at the end of the experiment. GLP‐1 (32–36) amide exerted favorable protective actions in streptozotocin‐induced diabetic mice. The peptide curtailed weight gain and alleviates symptoms of polydipsia. These findings suggested the probable utility of GLP‐1 (32–36) amide, a peptide mimetic derived there from GLP‐1, for adjuvant treatment of diabetes.     

Antihyperglycaemic action of diosmin,a citrus flavonoid,is induced through endogenous β‐endorphin in type I‐like diabetic rats

Diosmin is one of the flavonoids contained in citrus and has been demonstrated to improve glucose metabolism in diabetic disorders. However, the mechanism(s) of diosmin in glucose regulation remain obscure. Therefore, we investigated the potential mechanism(s) for the antihyperglycaemic action of diosmin in streptozotocin‐induced diabetic rats (STZ‐diabetic rats). Diosmin lowered hyperglycaemia in a dose‐dependent manner in STZ‐diabetic rats. This action was inhibited by naloxone at a dose sufficient to block opioid receptors. Additionally, we determined the changes in plasma β‐endorphin‐like immunoreactivity (BER) using enzyme‐linked immunosorbent assay (ELISA). Diosmin also increased BER dose‐dependently in the same manner. Repeated treatment of STZ‐diabetic rats with diosmin for 1 week resulted in an increase in the expression of the glucose transporter subtype 4 (GLUT 4) in the soleus muscle and a reduction in the expression of phosphoenolpyruvate carboxykinase (PEPCK) in the liver. These effects were also inhibited by naloxone at a dose sufficient to block opioid receptors. Bilateral adrenalectomy in STZ‐diabetic rats eliminated the actions of diosmin, including both the reduction in hyperglycemia and the elevation of plasma BER. In conclusion, our results suggest that diosmin may act on the adrenal glands to enhance the secretion of β‐endorphin, which can stimulate the opioid receptors to attenuate hepatic gluconeogenesis and increase glucose uptake in soleus muscle, resulting in reduced hyperglycemia in STZ‐diabetic rats.     

Anti-diabetic and renoprotective effects of aliskiren in streptozotocin-induced diabetic nephropathy in female rats

Since chronic kidney disease due to diabetic nephropathy (DN) is becoming an ever larger health burden worldwide, more effective therapies are desperately needed. In the present study, the anti-diabetic and renoprotective effects of aliskiren have been evaluated in streptozotocin (STZ)-induced DN in rats. DN was induced by a single intraperitoneal injection of STZ (65 mg/kg). Three weeks after STZ, rats were divided into four groups; normal, diabetic, diabetic treated with gliclazide (10 mg/kg/day) for 1 month, and diabetic treated with aliskiren (50 mg/kg/day) for 1 month. At the end of the experiment, mean arterial blood pressure and heart rate were recorded. Rats were then euthanized and serum was separated for determination of glucose, insulin, kidney function tests, superoxide dismutase activity (SOD), adiponectin, and tumor necrosis factor-alpha (TNF-α). One kidney was used for estimation of malondialdehyde (MDA), reduced glutathione (GSH), and nitric oxide (NO) contents. Other kidney was used for histopathological study and immunohistochemical measurement of caspase-3 and transforming growth factor beta (TGF-β). In addition, islets of Langerhans were isolated from normal rats by collagenase digestion technique for in vitro study. Aliskiren normalized STZ-induced hyperglycemia, increased insulin level both in vivo and in vitro, normalized kidney function tests and blood pressure, and alleviated STZ-induced kidney histopathological changes. This could be related to the ability of aliskiren toward preserving hemodynamic changes and alleviating oxidative stress and inflammatory and apoptotic markers induced by STZ in rats. However, aliskiren was more effective than gliclazide in relieving STZ-induced DN. These findings support the beneficial effect of aliskiren treatment in DN which could be attributed to its anti-diabetic, renoprotective, antioxidant, anti-inflammatory, and anti-apoptotic effects. Moreover, clinical studies are required to establish the effectiveness of aliskiren treatment in patients suffering from hypertension and diabetes.     

Diethylcarbamazine: Possible therapeutic alternative in the treatment of alcoholic liver disease in C57BL/6 mice

Alcoholic liver disease is a major cause of chronic liver disease worldwide. Diethylcarbamazine (DEC) is a drug that has anti‐inflammatory properties due to its effects on the metabolism of arachidonic acid. The present study examined the anti‐inflammatory effects of DEC on the mechanisms of alcoholic liver disease. C57BL/6 mice were divided into seven groups: (i) control; (ii) DEC 50 mg/kg; (iii) alcohol; (iv) alcohol + DEC 50 mg/kg; (v) alcohol + celecoxib 50 mg/kg; (vi) alcohol + pyrrolidine dithiocarbamate 100 mg/kg; and (vii) alcohol + pyrrolidine dithiocarbamate 100 mg/kg + DEC 50 mg/kg. Liver fragments were stained with haemotoxylin–eosin and Sirius red, and processed for immunofluorescence, western blot, and immunohistochemistry. Serum was also collected for biochemical measurements. Alcohol induced liver damage, elevated collagen content, and increased expression of nuclear factor kappa‐light‐chain‐enhancer of activated B cells and inflammatory markers (tumour necrosis factor‐α, interferon‐γ, interleukin‐1β, inducible nitric oxide synthase, cyclooxygenases‐2, and transforming growth factor‐β). Treatment with DEC was able to reduce liver damage, collagen content, the expression of nuclear factor kappa‐light‐chain‐enhancer of activated B cells and inflammatory markers; it also ameliorated biochemistry parameters (total cholesterol, high‐density lipoprotein cholesterol, triglyceride content and aspartate aminotransferase) and increased the expression of anti‐inflammatory markers (p‐5′ adenosine monophosphate‐activated protein kinase and interleukin‐10). Future clinical trials may demonstrate that oral administration of DEC may be suitable for the treatment of alcoholic liver disease and other liver diseases.     

Tropisetron ameliorates early diabetic nephropathy in streptozotocin‐induced diabetic rats

It has been well established that oxidative stress and inflammation are involved in the pathogenesis of diabetic nephropathy. It has been shown that tropisetron exerts anti‐inflammatory and immunomodulatory properties. The current study was designed to investigate protective effects of tropisetron on early diabetic nephropathy in streptozotocin‐induced diabetic rats. Rats were divided into six groups: (i) untreated diabetic (streptozotocin group); (ii) untreated control; (iii) diabetic rats treated with tropisetron (3 mg/kg); (iv) normal rats treated with tropisetron (3 mg/kg); (v) diabetic rats treated with granisetron (3 mg/kg); and (vi) normal rats treated with granisetron (3 mg/kg); rats began receiving treatment at the time of diabetes induction for 2 weeks. At the termination of the experiments, bodyweight, kidney index, urinary albumin excretion, and glomerular filtration rate were measured. The levels of oxidative stress markers and tumour necrosis factor‐α were also determined. Streptozotocin‐treated animals showed significant loss of bodyweight and renal enlargement and dysfunction. Diabetic rats also exhibited an increase in malondialdehyde along with a significant decrease in glutathione, superoxide dismutase activity, and catalase activity. Furthermore, the diabetic animals demonstrated a significant rise in renal cortical, urinary tumour necrosis factor‐α, and urinary albumin excretion. Both granisetron and tropisetron decreased blood glucose in diabetic animals, but this decrease was not significant for granisetron. Treatment with tropisetron, but not granisetron, prevented increases in oxidative stress and tumour necrosis factor‐α, decreased urinary cytokine excretion and albuminuria, and improved renal morphological damage. In conclusion, the present study suggests that tropisetron may be a protective agent in early diabetic nephropathy, and its action is mediated, at least in part, by anti‐oxidative and anti‐inflammatory mechanisms that appear to be independent of the 5‐HT₃ receptor.     

Synthesis of 1,4‐Anthracene‐9,10‐dione Derivatives and Their Regulation of Nitric Oxide,IL‐1β and TNF‐α in Activated RAW264.7 Cells

Mitoxantrone is an anthracenedione antineoplastic and immunosuppressive agent approved for multiple sclerosis treatment. Novel mono‐ and disubstituted anthraquinone derivatives, analogues of mitoxantrone, were synthesized through the addition of lipophilic amino alcohols and evaluated for their effect on IL‐1β, TNF‐α and nitric oxide production by LPS/IFN‐γ‐stimulated RAW264.7 cells. The disubstituted 1,4‐anthracene‐9,10‐dione 10 showed significant inhibition of nitric oxide, TNF‐α and IL‐1β production at the concentration of 5 μg/mL, with a much lower cytotoxicity than mitoxantrone. The monosubstituted 3 , 4 , 11, 12 and 13 also displayed a moderate to good inhibitory capacity on IL‐1β production. However, the methylated compounds 11, 12 and 13 failed to inhibit the TNF‐α production, and compound 13 was the only one to decrease the production of nitric oxide. None of these derivatives was toxic at the tested concentrations. Compounds 10 and 13 had better inhibitory capacity of the inflammatory mediators analyzed, with reliable viability of the cells.     

Daphnetin inhibits TNF‐α and VEGF‐induced angiogenesis through inhibition of the IKKs/IκBα/NF‐κB,Src/FAK/ERK1/2 and Akt signalling pathways

Coumarins, identified as plant secondary metabolites possess diverse biological activities including anti‐angiogenic properties. Daphnetin (DAP), a plant derived dihydroxylated derivative of coumarin has shown significant pharmacological properties such as anticancer, anti‐arthritic and anti‐inflammatory. The present study was performed to investigate the anti‐angiogenic potential of DAP, focusing on the mechanism of action. The in vivo anti‐angiogenic potential of DAP was evaluated by vascular endothelial growth factor (VEGF)‐induced rat aortic ring (RAR) assay and chick chorioallantoic membrane (CAM) assay. For in vitro evaluation, wounding migration, transwell invasion, tube formation and apoptosis assays were performed on VEGF (8 ng/mL)‐induced human umbilical vein endothelial cells (HUVECs). The cellular mechanism of DAP was examined on TNFα (10 ng/mL) and VEGF‐induced HUVECs by extracting the mRNA and protein levels using RT‐qPCR and western blotting. Our data demonstrated that DAP inhibited the in vivo angiogenesis in the RAR and CAM assay. DAP also inhibited the different steps of angiogenesis, such as migration, invasion, and tube formation in HUVECs. DAP inhibited nuclear factor‐κB signalling together including TNF‐α induced IκBα degradation; phosphorylation of IκB kinase (IKKα/β) and translocation of the NF‐κB‐p65 protein. Furthermore, western blotting revealed that DAP significantly down‐regulated the VEGF‐induced signalling such as c‐Src, FAK, ERK1/2 and the related phosphorylation of protein kinase B (Akt) and VEGFR2 expressions. DAP reduced the elevated mRNA expression of iNOS, MMP2 and also, induced apoptosis in VEGF‐stimulated HUVECs by the caspase‐3 dependent pathway. Taken together, this study reveals that DAP may have novel prospective as a new multi‐targeted medication for the anti‐angiogenesis and cancer therapy.     

β‐LAPachone ameliorates doxorubicin‐induced cardiotoxicity via regulating autophagy and Nrf2 signalling pathways in mice

β‐LAPachone (B‐LAP) is a naphthoquinone that possesses antioxidant properties. In the present investigation, the protective effect of B‐LAP against doxorubicin (DOX)‐induced cardiotoxicity was examined in mice. Thirty‐five mice were divided into 5 groups: control group, B‐LAP (5 mg/kg) group, DOX (15 mg/kg) group, DOX+B‐LAP (2.5 mg/kg) group and DOX+B‐LAP (5 mg/kg) group. B‐LAP was administered orally for 14 days of experimental period. A single dose of DOX (15 mg/kg) was injected intraperitoneally on day 3. Cardiac function, histoarchitecture, indices of oxidative stress and circulating markers of cardiac injury were examined. B‐LAP (5 mg/kg) decreased serum levels of lactate dehydrogenase (LDH), creatine kinase MB (CK‐MB) and cardiac troponin I (cTnI), and ameliorated cardiac histopathological alterations. In addition to increasing cellular NAD⁺/NADH ratio, B‐LAP up‐regulated the cardiac levels of SIRT1, beclin‐1, p‐LKB1 and p‐AMPK, and reduced the cardiac levels of p‐mTOR, interleukin (IL)‐1β, TNF (tumour necrosis factor)‐α and caspase‐3. B‐LAP also elevated the nuclear accumulation of Nrf2 and simultaneously up‐regulated the protein levels of haem oxygenase (HO‐1) and glutathione S‐transferase (GST) in the hearts of DOX mice. While B‐LAP reduced malondialdehyde concentrations in heart of DOX‐treated mice, it further promoted the activities of cardiac superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT).In accordance with increased cell survival, B‐LAP significantly improved the cardiac function of DOX mice. Collectively, these findings underline the protective potential of B‐LAP against DOX‐induced cardiotoxicity by regulating autophagy and AMPK/Nrf2 signalling pathway in mice.     

Coadministration of β‐asarone and levodopa increases dopamine in rat brain by accelerating transformation of levodopa: A different mechanism from Madopar

The aim of the present study was to investigate the effect of coadministration of β‐asarone and levodopa (l ‐dopa) on increasing dopamine (DA) in the striatum of healthy rats. Rats were randomly divided into four groups: (i) a normal group, administered normal saline; (ii) a Madopar group, administered 75 mg/kg Madopar (l ‐dopa : benserazide, 4 : 1); (iii) an l ‐dopa group, administered 60 mg/kg l ‐dopa; and (iv) a group coadministered 15 mg/kg β‐asarone and 60 mg/kg l ‐dopa. All drugs (or normal saline) were administered intragastrically twice a day for 7 days. Then, plasma and striatum concentrations of DA, l ‐dopa, 5‐hydroxytryptamine (5‐HT), homovanillic acid (HVA), 3,4‐dihydroxyphenylacetic acid (DOPAC), tyrosine hydroxylase (TH), catechol‐O‐methyltransferase (COMT) and monoamine oxidase B (MAO‐B) were determined. In the group coadministered β‐asarone and l ‐dopa, there was a decline in plasma and striatal concentrations of l ‐dopa; however, DA and DOPAC concentrations increased in the striatum and plasma and plasma HVA concentrations increased, whereas there was no significant change in striatal levels. Concentrations of 5‐HT in the striatum and plasma were similar in the coadministered and Madopar‐treated groups. In addition, plasma and striatal COMT levels decreased after coadministration of β‐asarone and l ‐dopa, whereas there were no significant differences in MAO‐B concentrations among groups. Furthermore, coadministration of β‐asarone and l ‐dopa increased plasma TH concentrations. Altogether, β‐asarone affects the conversion of l ‐dopa to DA by modulating COMT activity and DA metabolism. The mechanism of coadministration is different from that of Madopar in Parkinson's disease (PD) treatment. Thus, the coadministration of β‐asarone and l ‐dopa may be beneficial in the treatment of PD.     

Hypoxia inducible factor‐1α inhibition produced anti‐allodynia effect and suppressed inflammatory cytokine production in early stage of mouse complex regional pain syndrome model

Complex regional pain syndrome (CRPS) is related to microcirculation impairment associated with tissue hypoxia and peripheral cytokine overproduction in the affected limb. Previous studies suggest that the pathogenesis involves hypoxia inducible factor‐1α (HIF‐1α) and exaggerated regional inflammatory response. 1‐methylpropyl 2‐imidazolyl disulfide (PX‐12) acts as the thioredoxin‐1 (Trx‐1) inhibitor and decreases the level of HIF‐1α, and can rapidly be metabolized for Trx‐1 redox inactivation. This study hypothesized that PX‐12 can decrease the cytokine production for nociceptive sensitization in the hypoxia‐induced pain model. CD1 mice weighing around 30 g were used. The animal CRPS model was developed via the chronic post‐ischaemic pain (CPIP) model. The model was induced by using O‐rings on the ankles of the mice hind limbs to produce 3‐h ischaemia–reperfusion injury on the paw. PX‐12 (25 mg/kg, 5 mg/kg) was given through tail vein injection immediately after ischaemia. Animal behaviour was tested using the von Frey method for 7 days. Local paw skin tissue was harvest from three groups (control, 5 mg/kg, 25 mg/kg) 2 h after injection of PX‐12. The protein expression of interleukin‐1β (IL‐1β) and HIF‐1α was analysed with the Western blotting method. Mice significantly present an anti‐allodynia effect in a dose‐related manner after the PX‐12 administration. Furthermore, PX‐12 not only decreased the expression of HIF‐1α but also decreased the expression of IL‐1β over the injured palm. This study, therefore, shows the first evidence of the anti‐allodynia effect of PX‐12 in a CPIP animal model for pain behaviour. The study concluded that inhibition of HIF‐1α may produce an analgesic effect and the associated suppression of inflammatory cytokine IL‐1β in a CPIP model.     

Tracking anti‐fibrotic pathways of nilotinib and imatinib in experimentally induced liver fibrosis: An insight

The tyrosine kinase inhibitors imatinib and nilotinib have been suggested to have promising antifibrotic activity in experimental models of liver fibrosis. The aim of the present study was to investigate new pathways underlying this beneficial effect. Hepatic injury was induced in male Wistar rats by intraperitoneal injection of CCl₄ for 12 weeks. During the last 8 weeks of treatment, rats were also injected daily intraperitoneally with 20 mg/kg imatinib or 20, 10 or 5 mg/kg nilotinib. At the end of treatment, effects on fibrosis were assessed by measuring serum fibrotic markers and profibrogenic cytokines, as well as by histopathological examination. Possible anti‐inflammatory effects were estimated by measuring levels of inflammatory cytokines in liver tissue. Liver expression of α‐smooth muscle actin, transforming growth factor (TGF)‐β1 antibodies and platelet‐derived growth factor receptor β (PDGFRβ) was evaluated by immunohistochemical staining techniques. Nilotinib (5 and 10 mg/kg) significantly (P < 0.05) decreased all serum fibrotic markers measured, but 20 mg/kg of either nilotinib or imatinib had limited effects. At all doses tested, nilotinib significantly (P < 0.05) decreased the CCl₄‐induced increases in tissue inflammatory cytokines. Furthermore, 5 and 10 mg/kg nilotinib significantly decreased TGF‐β1 levels and tissue expression of its antibody, as well expression of PDGFRβ. In conclusion, low doses (5 and 10 but not 20 mg/kg) of nilotinib, rather than imatinib, can control hepatic fibrosis by regulating levels of proinflammatory cytokines, primarily interleukin (IL)‐1 and IL‐6. Nilotinib also controls the signalling pathways of profibrogenic cytokines by lowering TGF‐β1 levels and decreasing expression of PDGFRβ.     

Surgery‐induced changes in rat IL‐1β and acetylcholine metabolism: role of physostigmine

Pharmacological enhancement of cholinergic activity following administration of physostigmine is known to induce protective effects generally. However, it is unclear whether the effect of physostigmine on inflammation and acetylcholine (ACh) metabolism is related to different types of surgical intervention or anaesthesia alone. To investigate this, rats were subjected to partial liver resection (PLR) or sham surgery, with a control group receiving anaesthesia alone. Half of each treatment group received a single intra‐operative dose of physostigmine (0.04 mg/kg); the others received placebo. Acetylcholinesterase (AChE) activity and plasma and brain concentrations of interleukin (IL)‐1β and ACh were determined. Both PLR and sham operation induced a time‐dependent increase in plasma concentrations of IL‐1β compared with rats receiving anaesthesia alone (3.9‐ and 4.8‐fold increases, respectively). In the brain, IL‐1β concentrations had increased approximately twofold after surgery compared with the control group. Blood AChE was transiently decreased after surgery. Brain AChE activity increased 1.3‐fold (P = 0.014) only after PLR; consequently, cerebral ACh concentrations were significantly reduced. Physostigmine administration significantly reduced IL‐1β and AChE levels. Cerebral ACh concentrations were markedly increased from 544 ± 122 ng/mg protein following placebo administration to 654 ± 93 ng/mg protein after physostigmine administrations (P < 0.001). We conclude that a single dose of physostigmine intra‐operatively has a sustained anti‐inflammatory effect (up to 120 min after injection) that is especially pronounced under the conditions of PLR surgery. In addition to its protective peripheral action, physostigmine exerts a neuroprotective action by increasing levels of the neurotransmitter ACh.     

The furoxan nitric oxide donor,PRG150, evokes dose‐dependent analgesia in a rat model of painful diabetic neuropathy

Painful diabetic neuropathy (PDN) is a type of peripheral neuropathic pain that is often intractable. Elevated nitric oxide (NO) from neuronal and non‐neuronal sources in the somatosensory system is implicated in the pathobiology of peripheral neuropathic pain. However, in diabetes, nitrergic nerve degeneration to deplete NO bioactivity appears causal in the pathogenesis of irreversible autonomic neuropathy, another long term complication of diabetes. Hence, this study hypothesized that progressive NO depletion may underpin the pathobiology of PDN and that NO donors may alleviate PDN. Diabetes was induced in rats with intravenous streptozotocin (STZ) at 70 mg/kg and confirmed if blood glucose levels (BGLs) on day 10 post‐STZ were ≥15 mmol/L. Analgesic efficacy of subcutaneous (s.c.) bolus doses of the furoxan NO donor, PRG150 was assessed in the STZ‐diabetic rat model of PDN at 10‐, 14‐ and 24‐weeks post‐STZ relative to the sydnominine NO donor, SIN‐1 and its prodrug, molsidomine. PRG150 produced dose‐dependent analgesia in STZ‐diabetic rats whereas SIN‐1 and molsidomine evoked neuro‐excitatory side‐effects, but not analgesia. The 1000‐fold larger doses of PRG150 needed to produce analgesia at 14‐ and 24‐weeks (800 pmol/kg) c.f. 10‐weeks (8 fmol/kg) post‐STZ in rats, suggest that progressive NO depletion is also causal in PDN. Importantly, doses of PRG150 up to 10 000 fold higher than the analgesic dose did not produce hypotension in rats. The 50‐fold greater release of NO by SIN‐1 c.f. PRG150 in vitro, may underpin the neuro‐excitatory rather than analgesic effects of SIN‐1/molsidomine. PRG150 is worthy of further investigation as a potential novel analgesic for PDN.     

Chronic consumption of a high‐fat diet rich in corn oil activates intrinsic cell death pathway and induces several ultrastructural changes in the atria of healthy and type 1 diabetic rat

This study investigates the effect of chronic consumption of a high‐fat diet rich in corn oil (CO‐HFD) on atrial cells ultrastructure, antioxidant levels and markers of intrinsic cell death of both control and type 1 diabetes mellitus (T1DM)‐induced rats. Adult male rats (10 rats/group) were divided into four groups: control fed standard diet (STD) (3.82 kcal/g, 9.4% fat), CO‐HFD (5.4 kcal/g, 40% fat), T1DM fed STD, and T1DM + CO‐HFD. CO‐HFD and T1DM alone or in combination impaired systolic and diastolic functions of rats and significantly reduced levels of GSH and the activity of SOD, enhanced lipid peroxidation, increased protein levels of P53, Bax, cleaved caspase‐3, and ANF and decreased levels of Bcl‐2 in their atria. Concomitantly, atrial cells exhibited fragmentation of the myofibrils, disorganized mitochondria, decreased number of atrionatriuretic factor (ANF) granules, and loss of gap junctions accompanied by changes in capillary walls. Among all treatments, the severity of all these findings was more severe in T1DM and most profound in the atria of T1DM + CO‐HFD. In conclusion, chronic consumption of CO‐HFD by T1DM‐induced rats elicits significant biochemical and ultrastructural damage to rat atrial cells accompanied by elevated oxidative stress and mitochondria‐mediated cell death.     

RNAi Silencing of IL‐1β and TNF‐α in the Treatment of Post‐traumatic Arthritis in Rabbits

Post‐traumatic arthritis is a secondary complication to severe joint trauma. With the disease progression, it may eventually lead to osteoarthritis in patients whose age is considerably younger than patients with traditional bone arthritis. The main objective of this study was to explore the feasibility of using lentiviral‐mediated RNA interference silencing of IL‐1β and TNF‐α to treat post‐traumatic arthritis in rabbits. About 48 New Zealand rabbits underwent bilateral knee joint surgery to stimulate traumatic arthritis. They were then randomly divided into four groups of 12 rabbits each. The histopathology of the cartilage was observed, and the changes were assessed by Mankin scoring. ELISA was used to detect the expression of IL‐1β and TNF‐α in the synovial fluid. (i) Compared with the control group, the transfection and co‐transfected groups displayed reduced cartilage damage and speed of degeneration. The co‐transfected group showed the greatest alleviation of symptoms. The Mankin score was statistically different (p < 0.01). (ii) Compared with the control group, the expression of IL‐1β or TNF‐α was reduced in the respective transfection groups (p < 0.01 in both groups) and IL‐1β and TNF‐α were reduced in the co‐transfected group (p < 0.01). The co‐transfected group showed the lowest expression of the three experimental groups of both IL‐1β and TNF‐α (p < 0.01). Lentivirus‐mediated RNA interference can knock down the expression of IL‐1β and TNF‐α in joint fluids and, in a synergistic effect when two siRNAs are co‐transfected, ease cartilage degeneration.     

KCNJ11 E23K variant is associated with the therapeutic effect of sulphonylureas in Chinese type 2 diabetic patients

The aim of the present study was to investigate the effect of the E23K variant of the potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) gene on gliclazide modified release (MR) treatment in newly diagnosed patients with type 2 diabetes mellitus (T2DM). A total of 108 diabetic patients with no history of antidiabetic medication was treated with gliclazide MR for 16 weeks and underwent follow up at Weeks 2, 4, 8, 12 and 16. All patients were genotyped for KCNJ11 E23K (rs5219). At baseline, patients with the KK genotype had higher blood glucose and lower serum insulin levels after oral glucose administration than patients with the EE and EK genotypes (P < 0.05 for all). During treatment, individuals with the KK genotype had lower fasting glucose levels and were more likely to attain the target fasting glucose level (P_{log rank} = 0.028) than E allele carriers. Patients with the KK genotype had larger augmentations in changes (Δ) in acute insulin response (P = 0.049) and Δ body mass index (P = 0.003). Moreover, patients with the EK genotype had a lower variance in changes in fasting insulin levels (P = 0.049) and homeostasis model assessment of β‐cell function (P = 0.021) than those with the KK genotype. The findings of the present study suggest that the KCNJ11 E23K variant is associated with a greater effect of sulphonylurea treatment in newly diagnosed Chinese patients with T2DM.     

Stanozolol promotes lipid deposition in the aorta through an imbalance in inflammatory cytokines and oxidative status in LDLr knockout mice fed a normal diet

The aim of the study was to evaluate the effect of an anabolic steroid, stanozolol, in a model of atherosclerosis and to investigate the involvement of the modulation of the inflammatory cytokines and oxidative stress in vascular lipid deposition. Low‐density lipid receptor‐deficient (LDLr?/?) mice were fed a standard chow diet and were each week injected subcutaneously either saline (control C group) or 20 mg/kg stanozolol (S group). After 8 weeks, the levels of cholesterol, oxidized LDL (OxLDL) and cytokines were measured in plasma, lipid deposition in aorta was evaluated by en face analysis, and thiobarbituric acid‐reactive substances and oxidation protein were determined in liver. The S group demonstrated increases in vascular lipid deposition, triglycerides and non‐HDL cholesterol levels. Stanozolol increased tumour necrosis factor alpha (TNF‐α) and decreased interleukin‐10 as well as increased the TNF‐α/IL‐10 ratio. Furthermore, oxidative stress was observed in the S group, as indicated by an increase in the plasma OxLDL, as well as by lipid peroxidation and oxidation of proteins in the liver. Chronic treatment with stanozolol promoted lipid deposition in the LDLr^?/? mice that could be attributed to a modification of the circulating cytokine levels and systemic oxidative stress. Our results suggest that the anabolic steroid stanozolol in the absence of functional LDL receptors by increasing systemic inflammation and oxidative stress may increase the risk of development and progression of atherosclerosis.     

Doxazosin down‐regulates sodium‐glucose cotransporter‐2 and exerts a renoprotective effect in rat models of acute renal injury

Sodium‐glucose cotransporter‐2 (SGLT2) is known to be involved in the progression of acute renal injury (ARI) and is regulated by different mediators in the kidneys including extracellular signal‐regulated kinase (ERK), hypoxia‐inducible factor 1 alpha (HIF1α) and prostaglandin E2 (PGE2). In the present study, we investigated the possible protective effect of doxazosin on renal ischaemia/reperfusion (IR) and glycerol‐induced ARI by determining its effect on SGLT2 via modifying ERK‐HIF1α pathway and/or PGE2. Rats were divided into control, sham or IR where the rats received the vehicle, doxazosin (8 mg/kg) or the SGLT2 inhibitor, dapagliflozin (10 mg/kg) for 3 days followed by 45 minutes bilateral renal ischaemia then 24 hours reperfusion. Another group of rats received the vehicle, doxazosin or dapagliflozin for three days followed by injection of 50% glycerol (8 mL/kg, IM) or saline. Kidney function tests, systolic blood pressure (SBP), oxidative stress markers (malondialdehyde [MDA] and NADPH oxidase), nitric oxide (NO), inducible nitric oxide synthase (iNOS), HIF1α, ERK phosphorylation and PGE2 levels were determined. Additionally, renal sections were used for immunological expression of SGLT2. ARI rats showed significantly increased SBP; worsened kidney function tests; increased oxidative stress, iNOS, NO, HIF1α levels; and decreased PGE2 and ERK phosphorylation along with up‐regulated SGLT2. Doxazosin treatment protected against the kidney damage and attenuated the associated biochemical changes. Doxazosin has a direct renoprotective effect possibly by down‐regulating SGLT2.     

Design,Synthesis, and Biological Evaluation of 1‐(thiophen‐2‐yl)‐9H‐pyrido[3,4‐b]indole Derivatives as Anti‐HIV‐1 Agents

A novel series of 1‐(thiophen‐2‐yl)‐9H‐pyrido [3,4‐b]indole derivatives were synthesized using DL‐tryptophan as starting material. All the compounds were characterized by spectral analysis such as ¹H NMR, Mass, IR, elemental analysis and evaluated for inhibitory potency against HIV‐1 replication. Among the reported analogues, compound 7g exhibited significant anti‐HIV activity with EC₅₀ 0.53 μm and selectivity index 483; compounds 7e , 7i , and 7o displayed moderate activity with EC₅₀ 3.8, 3.8, and 2.8 μm and selectivity index >105, >105, and 3.85, respectively. Interestingly, compound 7g inhibited p24 antigen expression in acute HIV‐1_IIIB infected cell line C8166 with EC₅₀ 1.1 μm . In this study, we also reported the Lipinski rule of 5 parameters, predicted toxicity profile, drug‐likeness, and drug score of the synthesized analogues.