Physiological Effects of a Novel Immune Stimulator Drug, (1,4)‐α‐d‐Glucan,in Rats

Abstract: The (1,4)‐α‐d ‐glucan (α‐d ‐glucan), derived from medicinal plant, Tinospora cordifolia, activates human lymphocytes with downstream synthesis of the pro‐ and anti‐inflammatory cytokines, in vitro. We investigated physiological and immunological effects of a low and a high dose of α‐d ‐glucan (0.5 and 10 mg/kg), in vivo, testing the hypothesis that intravenous administration of α‐d ‐glucan does not affect haemodynamic, respiratory, haematological, and immune responses in normal rats. Male rats (300–400 g) were anaesthetized, tracheostomized, and catheterized in one femoral artery and vein. The mean arterial blood pressure and heart rate were continuously recorded. The baselines for gas exchange, differential blood cell count, and plasma concentration of TNF‐α, IL‐1β, IL‐4, IL‐6, and IFN‐γ were determined. Rats were then randomly assigned to controls (n = 7), a low dose (0.5 mg/kg; n = 10), and a high dose (10 mg/kg; n = 7) of α‐d ‐glucan for a six 6 hr study period. Gas exchange, differential cell count, plasma concentration of TNF‐α, IL‐1β, IL‐4, IL‐6, and IFN‐γ, and mean arterial blood pressure values remained within physiological range. Intravenous administration of 10 mg/kg α‐d ‐glucan created tachycardia, associated with hyperventilation, and significant reductions in the blood haemoglobin and haematocrit concentrations. We suggest that these in vivo effects of α‐d ‐glucan should be considered for future clinical and/or experimental trials.     

Immunological Response to (1,4)‐α‐d‐Glucan in the Lung and Spleen of Endotoxin‐Stimulated Juvenile Rats

Abstract: We investigated the effects of (1,4)‐α‐D‐glucan (α‐DG), a novel immune stimulatory drug from Tinospora cordifolia, on the concentration of pro‐ and anti‐inflammatory cytokines (interleukin [IL]‐1β, IL‐6, tumour necrosis factor‐α [TNF‐α], γ‐interferon [IFN‐γ] and IL‐10) in the lung and spleen of endotoxin‐stimulated juvenile rats. Experimental groups (n = 16/group) included controls with an intraperitoneal injection of saline, endotoxaemic rats with a non‐lethal dose of 10 mg/kg Escherichia coli endotoxin, and endotoxaemic rats treated with two doses of 10 mg/kg α‐DG, intraperitoneally, 2 and 4 hr after endotoxin injection. At 24 hr of treatment, rats were euthanized and lungs and spleen were removed for cytokines determination and lung injury. Endotoxaemia increased IL‐1β concentration by fivefold in both organs, while creating a moderate pulmonary hypercellularity (demonstrated by about 11% increase in the alveolar‐septal thickening and 11% decrease in the alveolar‐interstitial space ratio). In the lung, α‐DG treatment reduced concentrations of IL‐1β by 30% (p > 0.05), IL‐6 by 43% (p < 0.01), IFN‐γ by 46% (p < 0.01) and the anti‐inflammatory cytokine, IL‐10, by 31% (p > 0.05) compared to endotoxaemia. In the spleen, α‐DG treatment decreased the ratio of IL‐1β to IL‐10 by 55% (p < 0.05), demonstrating an anti‐inflammatory trend. These data suggest that α‐DG differentially modulates cytokine response in the lung and spleen and modifies the pro‐ and anti‐inflammatory balance during an early period of endotoxaemia in juvenile rats.     

Cyanidin‐3‐glucoside inhibits inflammatory activities in human fibroblast‐like synoviocytes and in mice with collagen‐induced arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint tissue inflammation. Cyanidin‐3‐glucoside (C3G) is a major component in the flavonoid family and has shown anti‐inflammatory, anti‐oxidant and anti‐tumour activity. In this study, we investigated the effects of C3G on lipopolysaccharides (LPS)‐induced inflammation on human rheumatoid fibroblast‐like synoviocytes (FLS) and on collagen‐induced arthritis (CIA) mice model. We treated FLS with C3G followed by LPS induction, the expressions of tumour necrosis factor alpha (TNF‐α), interleukin 1 beta (IL‐1β) and IL‐6 and the activation of nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) and mitogen‐activated protein kinase (MAPK) signalling pathway were analyzed. CIA was induced in mice and the arthritic mice were treated with C3G for 3 weeks. The disease severity was compared between control and C3G treated mice. The serum levels of TNF‐α, IL‐1β and IL‐6 were analyzed by ELISA. C3G inhibited LPS‐induced TNF‐α, IL‐1β and IL‐6 expression in FLS. Moreover, C3G inhibited LPS‐induced p65 production and IκBa, p38, ERK and JNK phosphorylation. Administration of C3G significantly attenuated disease in mice with CIA and decreased the serum level of TNF‐α, IL‐1β and IL‐6. C3G inhibited LPS‐induced inflammation in human FLS by inhibiting activation of NF‐κB and MAPK signalling pathway. C3G exhibited therapeutic effects in mice with CIA.     

Evaluation of the Effect of Hydroalcoholic Extract of Zingiber officinale Rhizomes in Rat Collagen‐induced Arthritis

Abstract: Patients with chronic, painful diseases often seek alternative therapy. The purpose of this study was to investigate the potential of hydroalcoholic extract of Zingiber officinale rhizomes (Z. officinale extract) to ameliorate inflammatory process in rat collagen‐induced arthritis. Our results show that Z. officinale extract in doses higher than 50 mg/kg/day intraperitoneally starting from the dose of booster immunization and for 26 days can ameliorate the clinical scores, disease incidence, joint temperature and swelling, and cartilage destruction, together with reduction of serum levels of interleukin (IL)‐1β, IL‐2, IL‐6, tumour necrosis factor‐α, and anti‐CII antibodies. Moreover, Z. officinale extract at the dose of 200 mg/kg/day was superior to 2 mg/kg/day of indomethacin at most of the measured parameters. These observations might make Z. officinale extract a good alternative to non‐steroidal anti‐inflammatory drugs for patients with rheumatoid arthritis.     

Pharmacological inhibition of TLR4/NF‐κB with TLR4‐IN‐C34 attenuated microcystin‐leucine arginine toxicity in bovine Sertoli cells

This study investigated the pharmacological inhibition of the toll‐like receptor 4 (TLR4) genes as a measure to attenuate microcystin‐LR (MC‐LR) reproductive toxicity. Bovine Sertoli cells were pretreated with TLR4‐IN‐C34 (C34) for 1 hour. Thereafter the pretreated and non‐pretreated Sertoli cells were cultured in medium containing 10% heat‐activated fetal bovine serum + 80 μg/L MC‐LR for 24 hours to assess the ability of TLR4‐IN‐C34 to attenuate the toxic effects of MC‐LR. The results showed that TLR4‐IN‐C34 inhibited MC‐LR‐induced mitochondria membrane damage, mitophagy and downregulation of blood‐testis barrier constituent proteins via TLR4/nuclear factor‐kappaB and mitochondria‐mediated apoptosis signaling pathway blockage. The downregulation of the mitochondria electron transport chain, energy production and DNA replication related genes (mt‐ND2, COX‐1, COX‐2, ACAT, mtTFA) and upregulation of inflammatory cytokines (interleukin [IL]‐6, tumor necrosis factor‐α, IL‐1β, interferon‐γ, IL‐4, IL‐10, IL‐13 and transforming growth factor β1) were modulated by TLR4‐IN‐C34. Taken together, we conclude that TLR4‐IN‐C34 inhibits MC‐LR‐related disruption of mitochondria membrane, mitophagy and downregulation of blood‐testis barrier proteins of the bovine Sertoli cell via cytochrome c release and TLR4 signaling blockage.     

α‐Lipoic acid prolongs survival and attenuates acute kidney injury in a rat model of sepsis

Acute kidney injury is a frequent and serious complication in patients with severe sepsis. α‐Lipoic acid (ALA), a naturally occurring dithiol compound, has been shown to possess anti‐inflammatory and anti‐oxidative properties. In the present study we investigated whether ALA could attenuate acute kidney injury and improve survival in a rat model of sepsis. Rats were subjected to caecal ligation and puncture (CLP) to induce sepsis. α‐Lipoic acid (200 mg/kg) was administered by oral gavage either immediately (early treatment) or 12 h after the surgical procedure (delayed treatment). Both early and delayed ALA treatment effectively prolonged survival, improved pathological damage in kidney tissues and reduced serum blood urea nitrogen and creatinine levels in CLP‐induced septic rats. Furthermore, early treatment with ALA markedly inhibited the release of tumour necrosis factor‐α, interleukin (IL)‐6 and IL‐1β into the serum and reduced mRNA and protein expression of inducible nitric oxide synthase and high mobility group box 1 in kidney tissues from CLP‐induced rats. Finally, CLP‐induced nuclear factor‐κB activation in kidney tissues was significantly suppressed by early ALA treatment. Together, the results indicate that ALA is able to reduce mortality and attenuate acute kidney injury associated with sepsis, possibly by anti‐inflammatory actions. α‐Lipoic acid may be a promising novel agent for the treatment of conditions associated with septic shock.     

D‐galactose‐induced toxicity associated senescence mitigated by alpinate oxyphyllae fructus fortified adipose‐derived mesenchymal stem cells

This study addresses the effect of D‐galactose‐induced toxicity associated senescence mitigated by alpinate oxyphyllae fructus (AOF; Alpinia oxyphylla Miq) extracts fortified with adipose‐derived mesenchymal stem cells (ADMSCs) in rats. Male 18 week‐old Wistar Kyoto (WKY) rats were used in this study. We analyzed cardiac fibrosis by Masson's trichrome staining. The tissue sections were dyed using hematoxylin and eosin (H&E). Tissue sections were stained for the restoration of Nrf2 expression in treatment groups by immunohistochemistry. Immunohistochemistry and western blotting analysis showed that AOF with ADMSCs could significantly reduce aging‐induced oxidative stress in D‐galactose‐induced aging rat hearts by inducing Nrf2 pathway. Reduction in ROS resulted in the suppression of inflammatory signals (p‐NF‐κB and IL‐6). Histopathological studies were showed an increased interstitium and collagen accumulation in aging‐induced heart sections. However, AOF and ADMSCs treated hearts were recovered from cardiac remodeling. Furthermore, hypertrophy and fibrosis associated markers were also significantly reduced (P < .05) in treatment groups. We speculate that ADMSCs might activate certain paracrine factors, which could target the upstream activator of aging associated cardiac complications and AOF might provide homing for these stem cells.     

Chronic moderate alcohol consumption relieves high‐fat high‐cholesterol diet‐induced liver fibrosis in a rat model

Nonalcoholic fatty liver disease is a worldwide health issue and chronic alcohol consumption may have different effects on this disease. This study explored the role of chronic moderate alcohol consumption on high‐fat high‐cholesterol (HFHC) diet‐induced liver fibrosis in a rodent model. Male Sprague–Dawley rats were divided into five groups: standard chow group, standard chow plus Er Guo Tou (EGT, a Chinese spirit made from fermented cereals) group, HFHC group, HFHC plus EGT group, and HFHC plus pure ethanol (EtOH) group. Rats were fed standard chow or HFHC chow for 12 weeks. EGT or pure ethanol was administrated at a daily dose of 4 g/kg body weight via intra‐gastric gavage from week 4. At the end of week 12, hematoxylin and eosin staining, Sirius red and immunohistochemistry of liver sections were examined. The hepatic expression of F4/80, TNF‐α, IL‐1β, IL‐6, CXCL1, CXCL2, α‐SMA, Collagen, TGF‐β, MMP2, MMP9, and TIMP1 was calculated. Both moderate EGT and pure ethanol did not increase plasma endotoxin in the portal vein comparing with the FHFC group. EGT and pure ethanol did not improve hepatic inflammation, but ameliorated liver fibrosis in histology. Moderate EGT and pure ethanol ameliorated HFHC diet‐induced activation of Kupffer cells and hepatic stellate cells. In conclusion, chronic moderate EGT and pure ethanol could ameliorate HFHC diet‐induced liver fibrosis.     

C‐phycocyanin protects against ethanol‐induced gastric ulcers in rats: Role of HMGB1/NLRP3/NF‐κB pathway

Gastric ulcer is a widespread inflammatory disease with high socio‐economic burden. C‐phycocyanin is one of the active constituents of Spirulina microalgae, and although it is well known for its antioxidant and anti‐inflammatory properties, its protective effects against gastric ulcer have not yet been identified. High‐mobility group box 1 (HMGB1) is a nuclear protein that, once secreted extracellularly, initiates several inflammatory reactions, and it is involved in the pathogenesis of gastric ulcer. The aim of the present study was to investigate the anti‐inflammatory and anti‐ulcerogenic effects of C‐phycocyanin against ethanol‐induced gastric ulcer targeting HMGB1/NLRP3/NF‐κB pathway. Ulcer induction showed increase in HMGB1 expression through activation of nucleotide‐binding domain and leucine‐rich repeat‐containing protein 3 (NLRP3) inflammasome and nuclear factor kappa p65 (NF‐κB p65). Moreover, oxidative stress and inflammatory markers were elevated in the ulcer‐treated group compared to the normal control group. However, pre‐treatment with C‐phycocyanin significantly reduced HMGB1 expression via suppression of NLRP3/NF‐κB, oxidative markers, IL‐1β, tumour necrosis factor‐α (TNF‐α) and ulcer index value. These results were consistent with histopathological and immunohistochemistry examination. Thus, C‐phycocyanin is a potential therapeutic strategy with anti‐inflammatory and anti‐ulcerogenic effects against ethanol‐induced gastric ulcer.     

Evaluations of lipid peroxidation and inflammation in short‐term glycerol‐induced acute kidney injury in rats

Rhabdomyolysis is characterised by acute kidney injury (AKI) resulting from skeletal muscle injury. Lipid peroxidation‐mediated oxidant injury and pro‐inflammatory cytokine‐mediated inflammatory response play critical roles in the pathogenesis of rhabdomyolysis‐induced AKI. The present study aimed to investigate the short‐term effects of both lipid peroxidation and inflammatory responses on rhabdomyolysis‐induced AKI in a rat model of glycerol‐induced rhabdomyolysis. Rhabdomyolysis was induced by the intramuscular injection of 50% glycerol in saline (10 mL/kg) into the hind limbs of rats. Rats were killed 1 or 3 hours after glycerol injection. Time‐dependent increases in serum biochemical parameters, including blood urea nitrogen, creatinine, lactate dehydrogenase and creatine phosphokinase levels, were observed 1 hour after glycerol injection. In kidneys, glycerol injection resulted in histopathological changes such as renal tubular injury and renal tubular myoglobin deposition. Levels of Nε‐(hexanoyl)lysine‐modified, 4‐hydroxy‐2‐nonenal‐modified, and nitrotyrosine‐modified proteins in rat kidneys were unaltered at 1 hour after glycerol injection, but increased significantly at 3 hours. Increases in renal nitric oxide production and the expression levels of inducible nitric oxide synthase, interleukin‐6 and tumour necrosis factor‐α in the renal parenchyma were observed at 1 hour after glycerol injection and plateaued at 3 hours. Our findings suggest that the pro‐inflammatory cytokine‐mediated inflammatory response may cause rhabdomyolysis‐induced AKI very shortly after glycerol injection, and lipid peroxidation‐mediated oxidant injury may promote the development of these pathophysiological processes.     

Bis‐(3‐hydroxyphenyl) diselenide inhibits LPS‐stimulated iNOS and COX‐2 expression in RAW 264.7 macrophage cells through the NF‐kB inactivation

Objectives Previously, we reported that diaryl diselenide compounds have strong inhibitory effects on lipopolysaccharide (LPS)‐induced nitric oxide (NO) production in macrophages. In this study, we investigated the molecular mechanisms underlying NO suppression and prostaglandin E₂ (PGE₂) production by diaryl diselenide compounds, bis‐(2‐hydroxyphenyl) diselenide (DSE‐A), bis‐(3‐hydroxyphenyl) diselenide (DSE‐B), bis‐(4‐hydroxyphenyl) diselenide (DSE‐C), dipyridyl diselenide (DSE‐D) and diphenyl diselenide (DSE‐E). Methods The effect of these compounds on NO suppression and PGE₂ production was investigated in RAW 264.7 macrophages. Key findings Our data indicate that of the above, DSE‐B most potently inhibits NO and PGE₂ production, and that it also significantly reduces the releases of tumour necrosis factor (TNF)‐α, interleukin(IL)‐1β and IL‐6. Consistent with these observations, DSE‐B also reduced the protein levels of inducible NO synthase (iNOS) and cyclooxygenase‐2 (COX‐2), and the mRNA levels of iNOS, COX‐2, TNF‐α, IL‐1β and IL‐6. Furthermore, DSE‐B inhibited LPS‐induced nuclear factor‐κB (NF‐κB) activation, which was associated with the prevention of the inhibitor κB‐α (IκB‐α) degradation and a subsequent reduction in nuclear p65 protein levels. Conclusions Taken together, our data suggest that the anti‐inflammatory properties of DSE‐B are due to reduction in the expression of iNOS, COX‐2, TNF‐α, IL‐1β and IL‐6 through the down‐regulation of NF‐κB binding activity.     

Synthesis and Anti‐Inflammatory Evaluation of Novel C66 Analogs for the Treatment of LPS‐Induced Acute Lung Injury

We previously reported a symmetric monocarbonyl analog of curcumin (MACs), C66, which demonstrated potential anti‐inflammatory activity and low toxicity. In continuation of our ongoing research, we designed and synthesized 34 asymmetric MACs based on C66 as a lead molecule. A majority of the C66 analogs effectively inhibited LPS induction of TNF‐α and IL‐6 expression. Additionally, a preliminary SAR was conducted. Furthermore, active compounds 4a11 and 4a16 were found to effectively reduce the W/D ratio in the lungs and the protein concentration in the bronchoalveolar lavage fluid (BALF). Meanwhile, a histopathological examination indicated that these two analogs significantly attenuate tissue injury in the lungs with LPS‐induced ALI rats. 4a11 and 4a16 also inhibited mRNA expression of several inflammatory cytokines, including TNF‐α, IL‐6, IL‐1β, COX‐2, ICAM‐1 and VCAM‐1, in the Beas‐2B cells after LPS challenge. Altogether, the data exhibit a series of new C66 analogs as promising anti‐inflammatory agents for the treatment of LPS‐induced ALI.     

Cryptotanshinone ameliorates renal ischaemia–reperfusion injury by inhibiting apoptosis and inflammatory response

Cryptotanshinone (CTS) is a natural compound from the Chinese herb Salvia miltiorrhiza. Previous studies demonstrated that CTS possesses anti‐apoptotic and anti‐inflammatory properties. However, its effects and underlying mechanism on renal ischaemia reperfusion (IR) injury remain unknown. In the present study, we investigated the effects of CTS on renal IR injury and its potential underlying mechanisms. Mice were randomized into four groups as follows: (a) sham operation + vehicle, (b) sham operation + CTS, (c) IR + vehicle, (d) IR + CTS. The CTS‐treated group were injected intraperitoneally with CTS (10 mg/kg/d) for 7 days prior to IR operation. Renal IR injury was induced by clamping the bilateral renal artery for 30 minutes followed by 24 hours of reperfusion. The mice were then killed to collect the serum and the kidneys for analysis. The results of the present study showed that CTS pretreatment significantly attenuates IR‐induced renal functional and morphological injuries, which was accompanied with inhibition of cell apoptosis and inflammatory response. Moreover, the phosphorylation of p38 mitogen‐activated protein kinase (MAPK) and the activation of nuclear factor‐κB (NF‐κB) signalling were inhibited by CTS. Therefore, CTS could be a useful therapeutic agent in the fight against renal IR injury.     

Rho Kinase Inhibitor,Fasudil, Attenuates Contrast‐induced Acute Kidney Injury

In this study, we tested the hypothesis that fasudil, a Rho kinase inhibitor, would protect against contrast‐induced acute kidney injury (CI‐AKI) in a mouse model and attempted to elucidate the mechanism involved. Mice subjected to unilateral ligation of the left anterior renal pedicle were divided into four groups: (1) control group, (2) CI‐AKI induced by contrast media (CM group), (3) CI‐AKI plus low‐dose fasudil (LD group) and (4) CI‐AKI plus high‐dose fasudil (HD group). Animals from groups 2–4 received iodixanol (4.0 g iodine/kg), and the control group received saline. At 12, 2 hr before iodixanol injection and 4 hr after iodixanol administration, the animals in groups 3–4 received 3 or 10 mg/kg fasudil, respectively. Renal blood flow, renal function parameters, kidney histology and the expression of proteins that regulates apoptosis and inflammation were determined 24 hr later. Fasudil treatment notably ameliorated contrast medium‐induced medullary damage, restored renal function, suppressed renal tubular apoptosis, ameliorated redox imbalance and DNA damage. Fasudil had a nephroprotective effect that was partially attributed to its anti‐inflammatory, anti‐apoptotic and antioxidant effects of inhibiting the Rho/ROCK pathway.     

In vivo studies on the immunotoxic effects of microcystins on rabbit

Microcystins (MCs) are the toxic molecules produced by common cyanobacterium in freshwater blooms. Their toxicities raise severe health issues in livestock and human beings. In current study, the immunotoxic effects of MC‐LR were investigated in rabbit through evaluating the dynamics of white blood cell (WBC) numbers and cytokine production such as interleukin‐3 (IL‐3), IL‐4, IL‐6, interferon‐γ (IFN‐γ), tumor necrosis factor‐α (TNF‐α). MCs at the high dose (50 μg MC‐LReq kg^?1) significantly induced increase in the WBC number but decrease in the Th1 (IFN‐γ, TNF‐α) and Th2 (IL‐3, IL‐4, IL‐6) production. In the low dose group(12.5 μg MC‐LReq kg^?1), the number of WBC and the production of IFN‐γ, IFN‐α, IL‐4, IL‐3, and IL‐6 increased gradually in first 12 h, reach the peaks at 12 h, and dropped after 24 h. Significantly positive correlations were found between the cytokines production of IL‐4 and IL‐6, IFN‐γ and IFN‐α, or IL‐4 and IFN‐γ. In conclusion, MC‐LR is able to disturb the rabbit immune system and there exists time‐dose response relationship in the MC‐LR‐eliciting perturbation, which probably give a better insight into investigating the immunotoxicity mechanisms of MCs in vivo. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.