Protective potential of fish oil supplementation against insulin resistance and pancreatic islet damage in STZ-induced Wistar rats.

Background: Fish oil, which is regarded as the primary source of omega-3 fatty acids, has been long studied for its potential as an antidiabetic therapy. However, its protective ability against insulin resistance and pancreatic islet alteration remains unclear and controversial. Aim: To investigate the beneficial effects of fish oil consumption on the progression of insulin resistance and pancreatic islet dysfunction in a rat model of diabetes. Methods: Diabetic rats model (n = 30) were divided into five groups and received; 1) NS injection + NS oral (normal control); 2) NS injection + 3 g/kg fish oil (fish oil control); 3) streptozotocin (STZ) injection + NS oral [diabetes control (DC)]; 4) STZ injection + 1 g/kg fish oil (DFO1); and 5) STZ injection + 3 g/kg fish oil (DFO3). Fasting blood insulin was analyzed by commercial rat insulin enzyme-linked immunosorbent assay; meanwhile, the determination of insulin sensitivity was calculated by homeostatic model assessment of insulin resistance (HOMA-IR) and homeostatic model assessment of beta-cell function. A histological study was conducted on pancreas tissue using H and E staining. Results: Fish oil supplementation reduced hyperglycemia and ameliorated HOMA-IR in STZ-induced animal models indicating that fish oil supplementation improved insulin sensitivity. Furthermore, animals treated with fish oil at a dose of 3 g/kg (DFO3) showed an enhancement in pancreatic islets, which was displayed by less abnormal structures than DC animals. This could imply that the administration of fish oil, especially rich in bioactive omega-3 fatty acids effectively inhibits insulin resistance and restore islet of Langerhans alteration in rats injected with STZ. Conclusion: Thus, the current study suggested that fish oil supplementation could support the treatment of diabetes but should not be considered as an alternative therapy.

Lauric acid improves hormonal profiles, antioxidant properties, sperm quality and histomorphometric changes in testis and epididymis of streptozotocin-induced diabetic infertility rats.

Lauric acid, a 12­carbon atom medium chain fatty acid (MCFA) has strong antioxidant and antidiabetic activities. However, whether lauric acid can ameliorate hyperglycaemia-induced male reproductive damage remains unclear. The study aimed to determine the optimal dose of lauric acid with glucose-lowering activity, antioxidant potential and tissue-protective effects on the testis and epididymis of streptozotocin (STZ)-induced diabetic rats. Hyperglycaemia was induced in Sprague Dawley rats by an intravenous injection of STZ at a dose of 40 mg/kg body weight (bwt). Lauric acid (25, 50 and 100 mg/kg bwt) was administered orally for eight weeks. Weekly fasting blood glucose (FBG), glucose tolerance and insulin sensitivity were examined. Hormonal profiles (insulin and testosterone), lipid peroxidation (MDA) and antioxidant enzyme (SOD and CAT) activities were measured in the serum, testis and epididymis. The reproductive analyses were evaluated based on sperm quality and histomorphometry. Lauric acid administration significantly improved FBG levels, glucose tolerance, hormones-related fertility and oxidant-antioxidant balance in the serum, testis and epididymis compared to untreated diabetic rats. Treatment with lauric acid preserved the testicular and epididymal histomorphometry, along with the significant improvements in sperm characteristics. It is shown for the first time that lauric acid treatment at 50 mg/kg bwt is the optimal dose for ameliorating hyperglycaemia-induced male reproductive complications. We conclude that lauric acid reduced hyperglycaemia by restoring insulin and glucose homeostasis, which attributes to the regeneration of tissue damage and sperm quality in STZ-induced diabetic rats. These findings support the correlation between oxidative stress and hyperglycaemia-induced male reproductive dysfunctions.

Ficus deltoidea ameliorates biochemical, hormonal, and histomorphometric changes in letrozole-induced polycystic ovarian syndrome rats.

BACKGROUND: Insulin resistance and hormonal imbalances are key features in the pathophysiology of polycystic ovarian syndrome (PCOS). We have previously shown that Ficus deltoidea var. deltoidea Jack (Moraceae) can improve insulin sensitivity and hormonal profile in PCOS female rats. However, biological characteristics underpinning the therapeutic effects of F. deltoidea for treating PCOS remain to be clarified. This study aims to investigate the biochemical, hormonal, and histomorphometric changes in letrozole (LTZ)-induced PCOS female rats following treatment with F. deltoidea. METHODS: PCOS was induced in rats except for normal control by administering LTZ at 1 mg/kg/day for 21 days. Methanolic extract of F. deltoidea leaf was then orally administered to the PCOS rats at the dose of 250, 500, or 1000 mg/kg/day, respectively for 15 consecutive days. Lipid profile was measured enzymatically in serum. The circulating concentrations of reproductive hormone and antioxidant enzymes were determined by ELISA assays. Ovarian and uterus histomorphometric changes were further observed by hematoxylin and eosin (H&E) staining. RESULTS: The results showed that treatment with F. deltoidea at the dose of 500 and 1000 mg/kg/day reduced insulin resistance, obesity indices, total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL), malondialdehyde (MDA), testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) to near-normal levels in PCOS rats. The levels of high-density lipoprotein cholesterol (HDL), estrogen, and superoxide dismutase (SOD) are also similar to those observed in normal control rats. Histomorphometric measurements confirmed that F. deltoidea increased the corpus luteum number and the endometrial thickness. CONCLUSIONS: F. deltoidea can reverse PCOS symptoms in female rats by improving insulin sensitivity, antioxidant activities, hormonal imbalance, and histological changes. These findings suggest the potential use of F. deltoidea as an adjuvant agent in the treatment program of PCOS.

Understanding the effects of Moringa oleifera in chronic unpredictable stressed zebrafish using metabolomics analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Moringa leaves have been used for thousands of years to maintain skin health and mental fitness. People also use it to relieves pain and stress. AIM OF THE STUDY: To determine the effects of Moringa oleifera leaves ethanol-aqueous (ratio 7:3) extract (MOLE) on the chronically stressed zebrafish. METHOD: The changes in the stress-related behaviour and the metabolic pathways in response to MOLE treatment in zebrafish were studied. A chronic unpredictable stress model was adopted in which zebrafish were induced with different stressors for 14 days. Stress-related behaviour was assessed using a depth-preference test and a light and dark test. Three doses of MOLE (500, 1000, and 2000 mg/L) were administered to the zebrafish. Upon sacrifice, the brains were harvested and processed for LC-MS QTOF based, global metabolomics analysis. RESULTS: We observed significant changes in the behavioural parameters, where the swimming time at the light phase and upper phase of the tank were increased in the chronically stressed zebrafish treated with MOLE compared to those zebrafish which were not treated. Further, distinctive metabolite profiles were observed in zebrafish with different treatments. Several pathways that shed light on effects of MOLE were identified. MOLE is believed to relieve stress by regulating pathways that are involved in the metabolism of purine, glutathione, arginine and proline, D-glutamine, and D-glutamate. CONCLUSION: MOLE is potentially an effective stress reliever. However, its effects in human needs to be confirmed with a systematic randomised control trial.

Ficus deltoidea promotes bone formation in streptozotocin-induced diabetic rats.

CONTEXT: Diabetes mellitus increases the risk of bone diseases including osteoporosis and osteoarthritis. We have previously demonstrated that Ficus deltoidea Jack (Moraceae) is capable of reducing hyperglycaemia. However, whether F. deltoidea could protect against diabetic osteoporosis remains to be determined. OBJECTIVE: The study examines the effect of F. deltoidea on bone histomorphometric parameters, oxidative stress, and turnover markers in diabetic rats. MATERIALS AND METHODS: Streptozotocin (STZ)-induced diabetic Sprague-Dawley rats (n = 6 animals per group) received one of the following treatments via gavage for 8 weeks: saline (diabetic control), metformin (1000 mg/kg bwt), and methanol leaves extract of F. deltoidea (1000 mg/kg bwt). A group of healthy rats served as normal control. The femoral bones were excised and scanned ex vivo using micro-computed tomography (micro-CT) for histomorphometric analysis. The serum levels of insulin, oxidative stress, and bone turnover markers were determined by ELISA assays. RESULTS: Treatment of diabetic rats with F. deltoidea could significantly increase bone mineral density (BMD) (from 526.98 ± 11.87 to 637.74 ± 3.90). Higher levels of insulin (2.41 ± 0.08 vs. 1.58 ± 0.16), osteocalcin (155.66 ± 4.11 vs. 14.35 ± 0.97), and total bone n-3 PUFA (2.34 ± 0.47 vs. 1.44 ± 0.18) in parallel with the presence of chondrocyte hypertrophy were also observed following F. deltoidea treatment compared to diabetic control. CONCLUSIONS: F. deltoidea could prevent diabetic osteoporosis by enhancing osteogenesis and inhibiting bone oxidative stress. These findings support the potential use of F. deltoidea for osteoporosis therapy in diabetes.