Effect of bitter gourd and spent turmeric on constituents of glycosaminoglycans in different tissues in streptozotocin induced diabetic rats

Bioactive polysaccharides from Momordica charantia as functional ingredients: a review of their extraction, bioactivities, structural-activity relationships, and application prospects

Momordica charantia L. is a well-known medicine and food homology plant with high pharmaceutical and nutritional values. Polysaccharides are carbohydrate polymers connected by glycosidic bonds, one of the key functional ingredients of M. charantia. Recently, M. charantia polysaccharides (MCPs) have attracted much attention from industries and researchers due to their anti-oxidant, anti-tumor, anti-diabetes, anti-bacteria, immunomodulatory, neuroprotection, and organ protection activities. However, the development and utilization of MCPs-based functional foods and medicines were hindered by the lack of a deeper understanding of the structure-activity relationship (SAR), structural modification, applications, and safety of MCPs. Herein, we provide an overview of the extraction, purification, structural characterization, bioactivities, and mechanisms of MCPs. Besides, SAR, toxicities, application, and influences of the modification associated with bioactivities are spotlighted, and the potential development and future study direction are scrutinized. This review provides knowledge and research underpinnings for the further research and application of MCPs as therapeutic agents and functional food additives.

Extraction methods, multiple biological activities, and related mechanisms of Momordica charantia polysaccharide: A review

Momordica Charantia Polysaccharide (MCP) is a key bioactive compound derived from bitter melon fruit. This review summarizes the advancements in MCP research, including extraction techniques, biological activities, and mechanisms. MCP can be extracted using various methods, and has demonstrated hypoglycemic, antioxidant, anti-inflammatory, and immunoregulatory effects. Research suggests that MCP may regulate metabolic enzymes, oxidative stress reactions, and inflammatory pathways. The review highlights the potential applications of MCP in areas such as anti-diabetes, antioxidant, anti-inflammatory, and immunoregulatory research. Future research should focus on elucidating the molecular mechanisms of MCP and optimizing extraction methods. This review provides a foundation for further research and utilization of MCP.

Studies on the partial characterization of extracted glycosaminoglycans from fish waste and its potentiality in modulating obesity through in-vitro and in-vivo

Glycosaminoglycans (GAGs) are bioactive polysaccharides or glycoconjugates found in the fish waste having significant health impacts. In the present study it has been attempted to extract GAGs from mackerel fish waste through chemical and enzymatic methods. Further, the extracted GAGs (e-GAGs) were analyzed for their composition (uronic acid, total sugar & sulfate), chemical characterization was carried out through techniques of scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) & Proton NMR. Further, probable major GAGs present was identified by enzymatic digestion. The biological potential of the extracted glycoconjugate was assessed further through in-vitro and in-vivo studies. In-vitro biological activity showed good lipase inhibition (IC₅₀, 2.6 mg/mL) and bile acid binding properties (dose-dependent). Lipid accumulation lowered in the e-GAGs differentiated 3T3L1 preadipocyte cells have also been observed. The high fat fed animal (in-vivo) study showed ameliorative effect via reducing blood sugar∼1.28↓, lipid profile↓, plasma insulin∼3.5↓, improved glucose tolerance, and homeostatic model assessment for insulin resistance (HOMA-IR, ∼3.0↓). Furthermore, elimination of bile acid (BA) due to GAG-BA binding properties resultant in removal of elevated fecal triglyceride and cholesterol suggesting its lipid lowering activity. Regulation of various proteins linked to carbohydrate and lipid metabolism including fatty acid synthase (FAS), low density lipoproteins receptor (LDL-R), 7α-hydroxylase, glucose transporter-4 (GLUT4) and Peroxisome proliferator- activated receptor gamma (PPAR-γ) were significant (p < 0.05) with e-GAGs treatment when compared to HFD group. Thus, the e-GAGs showed potential hypolipidemic activity through elimination of bile acid binding property together with regulating the specific protein related to obesity and its associated complications.

Momordica charantia: a popular health-promoting vegetable with multifunctionality

Products derived from edible medicinal plants have been used for centuries to prevent, treat, and even cure multiple diseases. Momordica charantia L., widely cultivated around the world, is a typical one bred for vegetables and medicinal usage. All parts of M. charantia possess important medicinal properties, including antidiabetic, anticancer, hypotensive, anti-obesity, antimicrobial, antihyperlipidemic, antioxidant, anti-inflammatory, immuno-modulatory, anthelmintic, neuro-protective, as well as hepato-protective properties both in vitro and in vivo. This review summarizes the active components and medicinal properties of M. charantia, especially the activities and mechanisms of its anti-diabetic and anti-cancer properties. The anti-diabetic properties involve inhibiting intestinal α-glucosidase and glucose transport, protecting islet β-cells, enhancing insulin secretion, increasing hepatic glucose disposal, decreasing gluconeogenesis, and even ameliorating insulin resistance. Moreover, the expressions of PPARs could also be activated and up-regulated. Meanwhile, its anticancer properties are mostly due to apoptosis, cell cycle arrest, and expression of serum factors associated with immunity. In this review, we aim to provide an overview of M. charantia and its benefits for development as a functional food.

Spent turmeric reduces fat mass in rats fed a high-fat diet

Indigestible carbohydrates may improve obesity. Spent turmeric contains high levels of dietary fibre and resistant starch (RS), which have fermentation potential in vitro. We hypothesised that indigestible carbohydrates in spent turmeric might prevent obesity development. In the first study, rats were administered 10% turmeric powder (TP) or spent turmeric powder (STP) in a high-fat (HF) diet for 28 d. In the second study, rats were fed 10% STP in a HF diet with or without antibiotics for 15 d. In the third study, rats were treated with a STP-containing suspension. In study 1, the TP and STP diet increased the caecal short-chain fatty acid (SCFA) content compared to that of a control diet. The lower energy intake in the TP and STP group was strongly related to the decrease in visceral fat weight. In study 2, after caecal fermentation suppression with antibiotics, STP treatment decreased the visceral fat mass. In study 3, the plasma glucose levels and incremental area under the curve (AUC) after ingestion of a STP-containing suspension were lower than those after ingestion of suspension alone. These findings suggest the reduction of carbohydrate absorption during the gastrointestinal passage after TP and STP treatment. Our data indicate that the reduced obesity development in rats fed a HF diet may be attributed to the low metabolisable energy density of carbohydrates in the spent turmeric, independent of SCFA-mediated factors.

Furosemide modifies heart hypertrophy and glycosaminoglycan myocardium content in a rat model of neurogenic hypertension

Hypertension is a major risk factor for atherogenesis and heart hypertrophy, both of which are associated with specific morphological and functional changes of the myocardium. Glycosaminoglycans (GAGs) are complex molecules involved both in tissue morphology and function. In the present study, we investigated the effects of neurogenic hypertension and subsequent antihypertensive treatment with furosemide, on heart hypertrophy and the content of GAGs in the myocardium. Neurogenic hypertension was achieved in male Wistar rats by bilateral aortic denervation (bAD). At days 2, 7 and 15 after surgery, animals were sacrificed and the hearts were dissected away, weighted, and homogenized. Total GAGs were assessed by measuring the uronic acid content colorimetrically and individual GAGs were isolated and characterized by enzymatic treatment, with GAG-degrading enzymes, using electrophoresis on polyacrylamide gradient gels and cellulose acetate membranes. In bAD-animals blood pressure, blood pressure lability, heart rate and heart weight were significantly increased 15 days postoperatively. These effects were prevented by treatment with furosemide. Major GAGs identified in the heart were chondroitin sulphates, heparin (H), heparan sulphate (HS) and hyaluronic acid. The content of uronic and the relative content of H and HS in the heart in bAD animals significantly decreased from day 2 to day 15 postoperatively. Furosemide prevented the bAD induced decrease in GAG content. Considering that H and HS are potent inhibitors of cardiomyocyte hypertrophy, our results indicate that heart hypertrophy induced by neurogenic hypertension may be associated with decreases in the relative content of heparin and heparan sulphate in the heart.

In vitro fermentation of spent turmeric powder with a mixed culture of pig faecal bacteria

The fermentation potential of spent turmeric was studied in in vitro swine faecal batch cultures. The spent turmeric residue (the enzyme-resistant fraction from spent turmeric, EST) was obtained through the use of the digestive enzymes amyloglucosidase and pancreatin and compared to cellulose and high-amylose starch (HAS) as carbon sources. EST showed significant increases in total anaerobes, bifidobacteria, lactobacilli and lactic acid bacteria populations compared to cellulose at 12, 24 and 48 h, and the total anaerobic level in the HAS group was significantly higher than that in the cellulose group at 24 and 48 h. However, a significant decrease in the coliform population was only found in the HAS group compared to the cellulose group at 48 h. The total short-chain fatty acid (SCFA) concentrations in the EST and HAS groups were significantly higher than that in the cellulose group at 12 h and 48 h. However, there was no significant difference in the total SCFA concentration between the EST and HAS groups at 12 h and 48 h. Ammonia and pH levels in the EST and HAS groups were significantly lower than those in the cellulose group at 24 and 48 h, but there was no significant difference between the EST and HAS groups. These results indicate that the fermentation potential of the enzyme-resistant fraction from spent turmeric is comparable to that of commercially established resistant starch.

Effect of spent turmeric on kidney glycoconjugates in streptozotocin-induced diabetic rats

Background

Curcumin known to have number of medicinal use and masked the fiber containing ukonan like active polysaccharide in turmeric and its pharmacological effect will be addressed on diabetic nephropathy particularly the glycoconjugates of extracellular components viz., glycoproteins and glycosaminoglycans - heparan sulfate (HS).

Methods

Male Wistar rats were maintained on AIN-76 diet containing 10% spent turmeric and were grouped into control and STZ induced diabetes SFC/TFC and SFD/TFD, respectively. Diabetic status was monitored using blood and urine, and at the end, harvested kidneys were used to study the amelioration of glycoprotiens (collagen) and HS by enzymatic digestion, spectrophotometric, hydroxyproline and agarose electrophoretic methods.

Results

In the present study spent turmeric (10%) fed diabetic rats showed improved glomerular filtration rate (50%), kidney enlargement (60%) and other glycoconjugate metabolism in kidney. Increased collagen content in diabetic group was observed by hydroxyproline estimation (24%) and periodic acid-Schiff’s (PAS) staining. Furthermore, elevated activities of enzymes involved in the synthesis and degradation of glycosaminoglycans (GAGs) were significantly lowered in spent turmeric fed diabetic group. Improvement in total GAGs (43%) and sulfate content (18%) followed by fractionation of GAGs using specific enzymes led to HS (28%) in the spent turmeric fed diabetic group, when compared to starch fed diabetic group and was further confirmed by electrophoresis of GAG.

Conclusion

These results clearly indicate beneficial role of spent turmeric in controlling glycoconjugates such as glycoproteins and heparan sulfate related kidney complications during diabetes.