Protective effects of Eucommia lignans against hypertensive renal injury by inhibiting expression of aldose reductase

Aim of the study

To investigate the protective effects and the underlying mechanism of Eucommia lignans against hypertensive renal injury.

Material and methods

Ten-week-old Wistar Kyoto rats and age matched spontaneously hypertension rats were used in the study. The SHR were randomly divided into 4 groups (n = 7 for each group) and received different treatment for 16 weeks, which including saline, Captopril, Epalrestat and Eucommia lignans, respectively. System blood pressures of the rats were monitored once every 4 weeks. N-Acetyl-β-d-glucosaminidase (NAG) activity and the ratio of albumin and urinary creatinine were chosen as the indices of kidney function. Then the structure and renal collagen type III expression of glomerular basement membrane were observed by microscopy and the renal aldose reductase (AR) expression was measured by immunohistochemistry. In vitro, the proliferation of mesangial cells induced by AngII was assayed by MTT, and the mRNA expression of AR was measured by RT-real-time PCR.

Results

The renal function, evaluated by NAG enzyme activity and the ratio of albumin to urinary creatinine, was significantly ameliorated by Eucommia lignans treatment. Meanwhile, Eucommia lignans decreased both the protein (P < 0.05) and the mRNA expressed lever of AR (P < 0.05). Eucommia lignans also decreased the high expression of collagen type III in SHR (P < 0.05) and inhibited the proliferation of renal mesangial cells induced by AngII (P < 0.05).

Conclusion

Eucommia lignans have protective effects against hypertensive renal injury, and the protective effects may be partly due to inhibition of aldose reductase.     

A new TCM formula FTZ lowers serum cholesterol by regulating HMG-CoA reductase and CYP7A1 in hyperlipidemic rats

Ethnopharmacological relevance

Based on a theory of Chinese Medicine, Regulating Gan (liver) to lower lipids that is in brief to regulate the lipid metabolic related factors in the liver will improve serum lipid profile, we have developed Fufang Zhenzhu Tiao Zhi (FTZ) which includes eight herbs that are quality assured. FTZ has been developed with the potential to correct abnormal lipid metabolism. This Chinese herbal medicine has been prescribed for 20 years, which has been issued patent and clinically proven for use in the treatment of dyslipidemia.

Aim of the study

To investigate the cholesterol-lowering effect and the mode of action of FTZ extract on high lipid diet induced hyperlipidemic rats.

Materials and methods

The FTZ was prepared by alcohol and water extraction of eight herbs that have been quality-controlled according to the protocol. The cholesterol-lowering effect of FTZ was evaluated on SD rats fed with high-lipid diet. RT-PCR and western blot were used to analyze the gene expression of cholesterol metabolism-related enzymes including HMG-CoA reductase and cholesterol 7α-hydroxylase (CYP7A1) in the livers of the rats. The activity of HMG-CoA reductase and CYP7A1 were assessed by colorimetrical method and by quantification of the cholesterol metabolite of CYP7A1 using HPLC analysis respectively.

Results and conclusions

FTZ significantly decreased the levels of serum total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), whilst elevated the serum high-density lipoprotein cholesterol (HDL-C) and decreased serum atherogenic index (A.I.) values in high lipid diet induced hyperlipidemic rats. Furthermore, FTZ showed significant antihyperlipidemic effect by at least three pathways in the high lipid diet induced hyperlipidemic rats: (1) upregulating the gene expression and activity of CYP7A1 which promotes the conversion of cholesterol into bile acid; (2) downregulating the gene expression and activity of HMG-CoA reductase to reduce de novo synthesis of cholesterol; (3) increasing the cholesterol excretion from feces. In these three pathways, HMG-CoA reductase and CYP7A1 are two pivotal enzymes in lipid cholesterol metabolism and are expressed mainly in hepatic cells, which support our new TCM treatment strategy: Modulating Liver to Treat Hyperlipemia.     

Preliminary study of antidiabetic activity of the methanolic leaf extract of Axonopus compressus (P. Beauv) in alloxan-induced diabetic rats

Ethnopharmacological relevance

Axonopus Compressus is commonly used by the people of Southern Nigeria to treat different ailment such as common cold and diabetes. This study therefore, evaluated the anti-diabetic effect of the methanolic leaf extract of the plant.

Materials and methods

Diabetes was induced in the rats by intraperitoneal (i.p.) injection of alloxan monohydrate at the dose of 180 mg/kg. Three test doses of the extract (250, 500 and 1000 mg/kg) administered per os through gastric gavage to the rats were used in the study. The activity was compared to a standard reference drug (glibenclamide, 2 mg/kg) and a negative control. Blood from the tail snip was used to measure the effects of the extract and drug at 0, 1, 3 and 6 h using autoanalyzer (AccuCheck Active^®) glucose kit.

Results

Methanolic leaf extract of Axonopus compressus at all the doses (250, 500 and 1000 mg/kg) used caused a respective time dependent and significant (p < 0.0001) reduction (by 31.5%, 19.8% and 24.5%) of the blood glucose levels in the diabetic rats when compared to the negative control group at the 6th hour. However, the reference drug (glibenclamide, 2 mg/kg) decreased the blood glucose levels by 69.9% and the tween 20 solution (negative control) increased the blood glucose level by 15.2% at the 6th hour. Moreso, the extract at the different test doses caused various degrees of reduction of the blood glucose levels of the test rats at 1st, 3rd and 6th hours when compared to the negative control rats.

Conclusion

The findings suggest that Axonopus compressus may possess antidiabetic property.     

Acute and sub-chronic toxicity study of standardized extract of Fumaria indica in rodents

Ethnopharmacological relevance

Despite Fumaria indica (FI) widespread medicinal uses in the Indian traditional medicine, no systematic study of the potential toxicity of the plant has been described.

Aim of the study

To assess acute and sub-chronic toxicity of a 50% ethanolic extract of FI in mice and rats respectively.

Materials and methods

In acute toxicity study, Swiss strain albino mice of either sex were administered orally FI doses of 1, 2.5 and 5 g/kg and observed for behavioural changes and mortality, if any. In sub-chronic toxicity study, Charles Foster albino rats of either sex were administered two doses of FI i.e., 100 and 400 mg/kg, p.o. for 30 consecutive days. During 30 days of treatment, rats were observed for any change in body weight and daily food and water intake. After 30 days, rats were sacrificed for haematological, biochemical and histopathology study. Control animals were administered 0.3% carboxymethyl cellulose (CMC) suspension by oral route.

Results

There was no mortality or abnormal behaviour, observed in acute toxicity study in mice at all the three dose levels. In sub-chronic toxicity study, FI did not produce any significant change in body weight and daily food and water intake of rats when compared to vehicle treated rats. Further, haematological and biochemical parameters were also found normal. Histopathological study revealed normal architecture of kidney and liver of FI treated rats.

Conclusions

FI extract, provisionally standardized on its fumarate contents, seems to fulfill a preclinical criterion necessary for its further development as a clinically useful adaptogen.     

Anti-osteoporosis activity of Cibotium barometz extract on ovariectomy-induced bone loss in rats

Ethnopharmacological relevance

Recent research has confirmed that Cibotium barometz could inhibits osteoclast formation with no affect on BMM cell viability. However, the in?uence of Cibotium barometz on osteoporosis in animals is relatively unknown. The purpose of this study is to systemically investigate the effects of Cibotium barometz extract (CBE) on ovariectomy-induced osteoporosis in rats.

Materials and methods

A total of Seventy-two 3-month-old female Sprague-Dawley rats were used and randomly divided into sham-operated group and five ovariectomized (OVX) groups: OVX with vehicle; OVX with 17β-estradiol (E2, 25 μg/kg/day); OVX with CBE of graded doses (100, 300, or 500 mg/kg/day). Daily oral administration of E2 or CBE began 4 weeks after the surgery and lasted for 16 weeks. Bone mass, bone turnover and strength were analyzed by DEXA, biochemical markers and three-point bending test. The trabecular bone microarchitecture was evaluated by MicroCT.

Results

CBE prevented total BMD decrease in the femur induced by OVX, which was accompanied by a significant decrease in skeletal remodeling, as was evidenced by the decreased levels of the bone turnover markers, such as osteocalcin (OC), alkaline phosphatese (ALP), deoxypyridinoline (DPD), and urinary Ca and P excretions. The treatment could also enhance the bone strength and prevent the deterioration of trabecular microarchitecture.

Conclusions

The present study indicated that Cibotium barometz extract might be a potential alternative medicine for the prevention and treatment of postmenopausal osteoporosis.     

Hypotensive effect of aqueous extract of Averrhoa carambola L. (Oxalidaceae) in rats: an in vivo and in vitro approach

Aim of the study

Averrhoa carambola L. (Oxalidaceae) leaves are used in Brazilian traditional medicine to treat hypertension. This study was conducted to evaluate the hypotensive effect of the aqueous extract of Averrhoa carambola (AEAc) and its underlying mechanisms in the isolated rat aorta.

Materials and methods

The effect of AEAc on the mean arterial pressure (MAP) was determined in vivo in anesthetized rats. In vitro, thoracic aortic rings were isolated and suspended in organ baths, and the effects of AEAc were studied by means of isometric tension recording experiments. In HPLC analysis, the fingerprint chromatogram of AEAc was established.

Results

In normotensive rats, AEAc (12.5-50.0 mg/kg, i.v.) induced dose-dependent hypotension. In vitro, AEAc caused a depression in the E_max response to phenylephrine without a change in sensibility. Also, in a depolarized Ca²⁺-free medium, AEAc inhibited CaCl₂-induced contractions and caused a concentration-dependent rightward shift of the response curves, indicating that AEAc inhibited the contractile mechanisms involving extracellular Ca²⁺ influx.

Conclusions

These results demonstrate the hypotensive effects of AEAc, and these effects may, in part, be due to the inhibition of Ca²⁺, which supports previous claims of its traditional use.     

Panax notoginseng saponins inhibit Zymosan A induced atherosclerosis by suppressing integrin expression, FAK activation and NF-κB translocation

Ethnopharmacological significance

Panax notoginseng saponins (PNS) are ingredients extracted from traditional Chinese medicinal herb Panax notoginseng. It has been demonstrated that PNS have extensive effects on the cardiovascular system, including inhibition of platelet aggregation, increasing blood flow, improving left ventricular diastolic function in hypertensive patients and anti-inflammatory effect.

Aim of study

Recent researches indicated that PNS administration inhibited foam cells’ formation. The present study was designed to study the effects of PNS on atherogenesis and to explore the relevant molecular mechanisms.

Materials and methods

The Zymosan A induced atherosclerosis models were used to investigate the anti-atherosclerosis effects of PNS. The integrin express array was used to check the changes of integrins. The foam cell formation was observed with transmission electron microscope. The effect of PNS on phosphorylation of FAK on threonine 397 and protein level of NF-κB was also evaluated in vitro.

Results

PNS treated rats had less plaque spots on the aortas compared with Zym induced group. The formation of foam cell was inhibited by PNS. Compared with Zym treated group, the expression of most integrin families decreased except Itgav and Itgb2 after PNS treatment. PNS inhibited phosphorylation of FAK on threonine 397 and translocation of NF-κB.

Conclusion

High fat diet together with Zym induces atherogenesis of rat. PNS inhibits zymosan A induced atherogenesis by suppressing FAK phosphorylation, integrins expression and NF-κB translocation.     

Hypoglycemic effect of bitter melon compared with metformin in newly diagnosed type 2 diabetes patients

Ethnopharmacological relevance

Bitter melon (Momordica charantia L.) has been widely used as an traditional medicine treatment for diabetic patients in Asia. In vitro and animal studies suggested its hypoglycemic activity, but limited human studies are available to support its use.

Aim of study

This study was conducted to assess the efficacy and safety of three doses of bitter melon compared with metformin.

Materials and methods

This is a 4-week, multicenter, randomized, double-blind, active-control trial. Patients were randomized into 4 groups to receive bitter melon 500 mg/day, 1000 mg/day, and 2000 mg/day or metformin 1000 mg/day. All patients were followed for 4 weeks.

Results

There was a significant decline in fructosamine at week 4 of the metformin group (−16.8; 95% CI, −31.2, −2.4 μmol/L) and the bitter melon 2000 mg/day group (−10.2; 95% CI, −19.1, −1.3 μmol/L). Bitter melon 500 and 1000 mg/day did not significantly decrease fructosamine levels (−3.5; 95% CI −11.7, 4.6 and −10.3; 95% CI −22.7, 2.2 μmol/L, respectively).

Conclusions

Bitter melon had a modest hypoglycemic effect and significantly reduced fructosamine levels from baseline among patients with type 2 diabetes who received 2000 mg/day. However, the hypoglycemic effect of bitter melon was less than metformin 1000 mg/day.     

A plasma metabonomic investigation into the intervention of volatile oil of Magnolia biondii Pamp on rat model of acute inflammation

Ethnopharmacological relevance

The dried flower buds of Magnolia biondii Pamp (Magnoliaceae) possesses significant anti-inflammatory activities.

Aim of the study

Volatile oil in Magnolia biondii Pamp (VOMbP) is considered to be important pharmacologically active individuals against acute inflammation, but its exact anti-inflammatory mechanism remains elusive. In this study, we aimed to investigate the intervention of VOMbP on rats with acute inflammation and explore the possible anti-inflammatory mechanisms of VOMbP with metabonomic strategy.

Materials and methods

Acute inflammation was induced by subcutaneously injection of carrageenan in the rats. Plasma was analyzed using gas chromatography-mass spectrometry (GC-MS), based on which the principal component analysis (PCA) and partial least squares-discriminate analysis (PLS-DA) models were established for metabonomic analysis.

Results

It was revealed that the pretreatment of VOMbP in acute inflammatory rats induces a substantial and characteristic change in their metabolic profiles. Some significantly changed metabolites, including hexadecanoic acid, linoleic acid, oleic acid, stearic acid, and cholesterol, were found to be reasonable in explaining the anti-inflammatory mechanism of VOMbP.

Conclusions

In all, it is likely that VOMbP intervenes the metabolic process of inflammatory rats by affecting the fatty acid and cholesterol metabolism. Our work also indicated that the metabonomics method is a promising tool for performing intervention and mechanism research of traditional Chinese medicines.     

Protective effect of Ilex latifolia, a major component of "kudingcha", against transient focal ischemia-induced neuronal damage in rats

Aims of the study

Ilex latifolia (Aquifoliaceae), a primary component of “kudingcha”, has been used in Chinese folk medicine to treat various kinds of diseases including headaches, inflammatory diseases, and cardiac ischemic injury. The present study investigated the protective effect of the ethanol extract of Ilex latifolia against transient, focal, ischemia-induced neuronal damage.

Materials and methods

Transient focal ischemia was induced by 2 h middle cerebral artery occlusion followed by 24 h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, brain infarction and neuronal death were measured by triphenyltetrazolium chloride and hematoxylin and eosin staining, respectively. Glutathione concentration and lipid peroxidation rate were measured. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), cyclooxygenase 2 (COX-2), and anti-apoptotic and pro-apoptotic proteins were detected by Western blot.

Results

Ilex latifolia (50-200 mg/kg) significantly reduced MCAO/reperfusion-induced infarction and edema formation, neurological deficits, and brain cell death. Depletion of glutathione level and lipid peroxidation induced by MCAO/reperfusion were inhibited by administration of Ilex latifolia. The increase of phosphorylated MAPKs, COX-2, and proapoptotic proteins and the decrease of antiapoptotic protein in MCAO/reperfusion rats were significantly inhibited by treatment with Ilex latifolia.

Conclusion

Ilex latifolia ameliorated ischemic injury induced by MCAO/reperfusion in rats, and this neuroprotective effect might be associated with its anti-apoptotic effect, resulting from anti-oxidative and anti-inflammatory actions.     

Cardioprotective effect of water and ethanol extract of Salvia miltiorrhiza in an experimental model of myocardial infarction

Ethnopharmacological relevance

Salvia miltiorrhiza has long been used in the traditional Chinese formulations for the treatment of heart ischemic diseases.

Aim of the study

We investigated the cardioprotective effect of purified Salvia miltiorrhiza extract (SME) in an experimental model of acute myocardial infarction.

Materials and methods

Following induction of acute myocardial infarction in rats by adminstration of isoproterenol, hemodynamic and electrocardiographic parameters were monitored and recorded continuously, cardiac enzymes and parameters of oxidative stress were measured, and histopathological examination of heart tissue was performed. Experiments were performed in rats treated with SME or vehicle, as well as in those treated with Fufang Danshen Tablet (FDT) as a positive control which has previously been shown to prevent myocardial ischemia.

Results

Isoproterenol-treated rats showed reductions in left ventricular systolic pressure as well as in maximum and minimum rate of developed left ventricular pressure, together with an increase in left ventricular end-diastolic pressure. They also demonstrated ST-segment elevation, together with increases in serum levels of lactate dehydrogenase, glutamic oxalacetic transaminase, creatine kinase and malondialdehyde, as well as decreases in serum activities of glutathione peroxidase and superoxide dismutase. Oral administration of SME (29.76 or 59.52 mg/kg) blunted all of the hemodynamic and biochemical changes induced by isoproterenol, as did FDT (1210 mg/kg). The protective effect of SME on isoproterenol-induced myocardial damage was further confirmed by histopathological examination.

Conclusions

Our results suggest that SME affords protection against isoproterenol-induced myocardial infarction.     

Diuretic, anti-inflammatory, and analgesic activities of the ethanol extract from Cynoglossum lanceolatum

Ethnopharmacological relevance

Cynoglossum lanceolatum Forsk. (Boraginaceae) has been used in folk medicine in china to treat acute nephritis, periodontitis, acute submandibular lymphadenitis, snake bite, etc. However, there have been no scientific reports in the modern literature on the diuretic, anti-inflammatory and analgesic effects of this plant. The objective of this study is to evaluate the above activities of the Cynoglossum lanceolatum extract (CLE) in animals.

Materials and methods

The diuretic effect of CLE was assessed in rats and rabbits. The anti-inflammatory activity was evaluated using fresh egg white-induced paw edema in rats, carrageenan-elicited paw edema in adrenalectomized rats, and dimethylbenzene-induced inflammation in mice. The analgesic action was estimated in mice using the acetic acid-induced writhing test and the hot-plate test. In addition, the acute oral toxicity of CLE was studied in mice.

Results

CLE strikingly and dose-dependently increased urine output of rats and rabbits, suppressed fresh egg white-induced paw edema in rats and carrageenan-elicited paw edema in adrenalectomized rats, reduced dimethylbenzene-induced ear edema in mice, inhibited the writhing response in mice, but did not increased reaction time of mice in the hot-plate test. No death of mice was observed when orally administered CLE up to 12 g/kg.

Conclusions

These findings propose that CLE has evident diuretic, anti-inflammatory, and non-central analgesic activities. Furthermore the anti-inflammatory action does not rely on endogenetic glucocorticoids regulated by hypothalamo-pituitary-adrenal axis. On the other hand, CLE also shows a favorable safety.     

In vitro growth stimulatory and in vivo wound healing studies on cycloartane-type saponins of Astragalus genus

Aim of the study

The present study was undertaken to evaluate the wound healing effects of the four chief saponins of Astragalus species [cycloastragenol (CA), astragaloside IV (AG), cyclocephaloside I (CCI) and cyclocanthoside E (CCE)].

Material and methods

Effects of cell viability and proliferation of the isolated compounds were evaluated by the MTT assay on human keratinocyte. The wound healing activity was studied by using in vitro wound healing, proliferation and migration scratch assay. In order to see in vivo effectiveness of the compounds, an animal study with Sprague-Dawley male rats at the age of 12 weeks was carried out, and then the main histological outcomes were investigated to observe reepithelization, neovascularization, and presence of inflammatory cells, granulation tissue amount and maturation.

Results

All the compounds increased both fibroblast proliferation and migration, but the effects were much superior for CA at 1 ng/ml concentration. Among the compounds, based on the histological findings, 5% CA preparation was found to be the most remarkable in vivo wound healing agent showing greater cell density, more regularly organized dermis and more newly formed blood vessels.

Conclusion

Results of this study indicate that the cycloartane-type saponins are the principal constituents responsible for wound healing activities of the roots of Astragalus species substantiating its use in traditional medicine.     

Increased sexual motivation in female rats treated with Humulus lupulus L. extract

Aim of the study

To evaluate the influence of Humulus lupulus extract on sexual behavior in female rats.

Materials and methods

Ovariectomized rats hormonally primed with estradiol benzoate (1.5 μg/rat) and progesterone (500 μg/rat) were acutely treated by oral gavage with Humulus lupulus extract dosed at 5, 10 and 25 mg/kg and then tested for partner preference and sexual receptivity.

Results

The administration of Humulus lupulus extract at the highest dose significantly increased the preference for the stimulus male during the partner preference test and the number of proceptive behaviors during the receptivity test, without affecting the lordosis response.

Conclusions

Humulus lupulus extract increased sexual motivation in hormone-primed female rats.     

In vivo antiulcer activity of the aqueous extract of Bauhinia purpurea leaf

Ethnopharmacological relevance

Bauhinia purpurea (Fabaceae) is a medicinal plant traditionally used to treat various ailments, including ulcers. In order to establish pharmacological properties of the leaf of Bauhinia purpurea, studies were performed on antiulcer activity of the plant's aqueous extract.

Materials and methods

The Bauhinia purpurea aqueous extract (BPAE) was prepared in the doses of 100, 500 and 1000 mg/kg. Antiulcer activity of BPAE was evaluated by absolute ethanol- and indomethacin-induced gastric ulcer, and pyloric ligation models. Acute toxicity was also carried out.

Results

BPAE, at the dose of 5000 mg/kg, did not cause any signs of toxicity to rats when given orally. Oral administration of BPAE exhibited antiulcer activity (p < 0.05) in all models used. However, the dose-dependent activity was observed only in the absolute ethanol-induced gastric ulcer model. Histological studies supported the observed antiulcer activity of BPAE. In pyloric ligation assay, BPAE increased the gastric wall mucus secretion.

Conclusions

The BPAE exhibits antiulcer activity, which could be due to the presence of saponins or sugar-free polyphenols, and, thus, confirmed the traditional uses of Bauhinia purpurea in the treatment of ulcers.     

Neuroprotective effect of Momordica charantia in global cerebral ischemia and reperfusion induced neuronal damage in diabetic mice

Ethnopharmacological relevance

Momordica charantia L. (Cucurbitaceae) fruits have been used traditionally for centuries, especially for treating diabetes and associated complications.

Aim of the study

The present study was performed to evaluate neuroprotective effect of lyophilized M. charantia fruit juice against global cerebral ischemia and reperfusion induced neuronal injury in diabetic mice.

Materials and methods

Global cerebral ischemia induced by occluding both common carotid arteries for 10 min followed by 24 h reperfusion was used to induce neuronal injury. Ischemia-reperfusion induced neuronal injury was evaluated in terms of cerebral infarct size, generation of free radicals measured as thiobarbaturic acid reactive substances (TBARS), and neurological functions measured as short term memory and motor activity.

Results

The cerebral oxidative stress and damage, and neurological deficits were dose dependently attenuated by pre-treatment with the lyophilized M. charantia juice (200-800 mg/kg, p.o., o.d.). Moreover, M. charantia also exhibited dose dependent antihyperglycemic activity in diabetic mice.

Conclusions

These results suggest that M. charantia has potent neuroprotective activity against global cerebral ischemia-reperfusion induced neuronal injury and consequent neurological deficits in diabetic mice.     

Anti-oxidation activity of the crude polysaccharides isolated from Polygonum Cillinerve (Nakai) Ohwi in immunosuppressed mice

Aim of the study

Polygonum Cillinerve (Nakai) Ohwi is commonly used in China for over 2000 years. Previous research has shown that the crude polysaccharides extracted from Polygonum Cillinerve (Nakai) Ohwi (PCCP) have the scavenging free radicals and anti-tumor activities in vitro. In present study, PCCP were further approached the perspective of their anti-oxidation in immunosuppressed mice.

Methods and materials

ICR mice were treated firstly with cyclophosphamide (CY, 150 mg/kg), 1 day later, treated with different dosages of PCCP or saline solution once daily for 21 days. Twenty-four hours later for the last drug administration, the animals were weighed, and then killed by decapitation. The liver, spleen, and thymus indices were investigated, and the biochemical parameters were evaluated for various tissues (liver, heart, and kidney).

Results

The administration of PCCP with gavage was able to overcome the cyclophosphamide-induced immunosuppression, and significantly to raise the TOC, CAT, SOD, and GSH-Px level. It also raised the liver, spleen, and thymus indices, and decreased the MDA level in mice.

Conclusions

PCCP possess the pronounced free radical-scavenging and antioxidant activities, and could play an important role in the prevention of oxidative damage in immunological system.     

Antidiabetic activity of alcoholic stem extract of Nervilia plicata in streptozotocin-nicotinamide induced type 2 diabetic rats

Ethnopharmacological relevance

Nervilia plicata (Orchidaceae) has long been used in the antidiabetic medicinal preparations of traditional healers of Wayanad (Kerala), but recuperative potential of the plant was remained undefined. We demonstrated the regenerative potential of the plant extract on kidney affected by type 2 diabetes besides lowering blood glucose.

Aim of the study

The aim of the current study was to investigate the recuperative and regenerative potential of alcoholic stem extract of Nervilia plicata on streptozotocin-nicotinamide induced type 2 diabetic models.

Materials and methods

Non insulin dependent diabetes mellitus (NIDDM) was induced in overnight fasted rats by intramuscular injection (IMI) of 60 mg/kg STZ and 120 mg/kg of nicotinamide after 5 min interval. Blood glucose was assessed by a glucometer, serum urea and creatinine levels were determined by diacetylmonooxime method and Jaffe reaction respectively. Kidney sections were taken and stained with Masson's tri-dye and Periodic Acid Schiff (PAS) and examined for structural changes. Also lipid peroxidation product (LPP) levels were determined as thio barbituric acid reactive substance levels (TBARS) method.

Results

On administration of 5 mg/kg of plant extract, blood glucose levels of the NIDDM rats showed 62.00 and 76.29% decrease in the blood glucose levels on day 0 and day 30 respectively. Damages caused to the kidney tissue were negligible or not seen. Serum urea and creatinine levels showed 61.49 and 70.96% decrease on day 30. LPP levels of kidney and pancreas showed 70.58 and 77.41% decrease respectively.

Conclusion

These results demonstrate significant antidiabetic and regenerative potential of the Nervilia plicata, justifying the use of plant in the indigenous system of medicine. Isolation and characterisation of the compound(s) playing pivotal role in the cure would open new vistas in the therapy of type 2 diabetes.     

Indigofera suffruticosa Mill as new source of healing agent: involvement of prostaglandin and mucus and heat shock proteins

Ethnopharmacological relevance

Indigofera suffruticosa is specie typical of the “Cerrado” or Brazilian savannah; it is a member of the Fabaceae family - in folkmedicine is used for gastric disorders, infection and inflammation.

Aim of the study

Ethyl acetate fraction (AcF) and aqueous fraction (AqF) of the methanolic extract of I. suffruticosa leaves were evaluated against acute gastric ulcer. The AcF fraction was selected to assess its activity in ulcer healing and its gastroprotective effects via mucus and gastric secretion.

Materials and methods

The gastroprotective action of AcF and AqF fractions were evaluated in a rodent experimental model. The action mechanisms, involvements of the antisecretory action, mucus and prostaglandin production, toxicological and healing activity of the AcF (100 mg/kg, p.o.) were evaluated. We also used histological analysis (HE and PAS) and immunohistochemical (PCNA and HSP-70) assays to evaluate the effects of I. suffruticosa.

Results

AcF significantly inhibited the gastric mucosal damage caused by ethanol. This effect was statistically significant in 100 mg/kg group compared vehicle. AcF did not interfered with gastric secretion, significantly increased the PGE₂ and mucus production (validated in PAS technique). The gastroprotection was attenuated by pretreatment with N-ethylmaleimide, but not L-NAME. In acid-acetic-induced ulcer model AcF accelerated ulcer healing. Immunohistochemistry analysis showed induction of proliferating cell (PCNA) and heat shock protein (HSP 70).

Conclusions

These results showed that AcF acted as gastroprotective agent stimulating prostaglandin, mucus and HSP70.