Preventive and Therapeutic Potentials of Anthocyanins in Diabetes and Associated Complications.

Diet is an essential factor affecting the development of and risk for diabetes mellitus. In search of preventative and therapeutic strategies, the potential role of certain foods and their bioactive compounds to prevent the pathogenesis associated with metabolic diseases is to be considered. Human consumption of anthocyanins is among the highest of all flavonoids. Epidemiological studies have suggested that the consumption of anthocyanins lowers the risk of diabetes and diabetic complications. Anthocyanins are important natural bioactive pigments responsible for red to blue colour of fruits, leaves, seeds, stems and flowers, which are present in a variety of plant species particularly in berries and cherries. A large number of bioactive anthocyanins, such as cyanidin, malvidin, delphinidin, pelargonidin, peonidin, petunidin and their metabolites have shown multiple biological activities with apparent effects on glucose absorption, glucose uptake, insulin secretion and sensitivity, on the enzymes involved in glucose metabolism, gene expressions, inflammatory mediators, glucose transporters in progression of diabetes and associated complications, such as diabetic retinopathy, nephropathy, neuropathy and diabetic vascular diseases. The versatility of the anthocyanins provides a promising approach for diabetes management than synthetic drugs. Here we summarize the effect of several anthocyanins on many in vitro, in vivo and clinical studies and also reveal the mechanisms which could prevent or reverse the underlying mechanisms of diabetic pathologies including promotion of antioxidant, antihyperlipidemic, anti-inflammatory and anti-apoptotic activities.

Anthocyanins: Multi-Target Agents for Prevention and Therapy of Chronic Diseases.

Anthocyanins, a flavonoid class of polyphenols, are water soluble dark colored natural pigments found in fruits and vegetables. Owing to their wide distribution in plant materials, dietary consumption of anthocyanins is high compared to other flavonoids. Anthocyanins, due to their multifaceted medicinal properties are the active components in many herbal folk medicines. As in vitro and in vivo results, animal models, and clinical trials in various cell lines suggest, anthocyanins possess antioxidant, antidiabetic, antihyperlipidemic, anti-inflammatory, anticarcinogenic, antiulcer, and preventive activities against cardiovascular diseases. Additionally, anthocyanins exhibit chemotherapeutic, cardioprotective, hepatoprotective, and neuroprotective activities. In the diet, anthocyanins are absorbed in the stomach and intestinal cells and rapidly detected in the plasma. These promising properties of anthocyanins may well provide health benefits against chronic diseases.

Delayed progression of diabetic cataractogenesis and retinopathy by Litchi chinensis in STZ-induced diabetic rats.

CONTEXT: The study was carried out to evaluate the effect of the aqueous fruit pericarp extract of Litchi chinensis (APLC) on parameters which leads to diabetic cataractogenesis and retinopathy in the streptozotocin-induced diabetic rats. OBJECTIVE: The objective of the study is to evaluate the APLC for in vivo antioxidant activity and its role in inhibiting the polyol pathway and formation of advanced glycation end products (AGEs). MATERIALS AND METHODS: The diabetic animals were treated with L. chinensis for a period of 12 weeks. At the end of 12 weeks, the animals were killed and the biochemical pathways involved in the pathogenesis of cataract such as oxidative stress by protein content, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and polyolpathway by aldose reductase (AR) in lens homogenates, alterations in protein carbonyl content (PCO) and AGEs in both serum and lens the APLC-treated diabetic rats were compared against diabetic control rats. Cataract progression due to hyperglycemia was monitored by slit lamp bio microscope and classified into four stages. Fundoscope test and retinal histopathology were done for assessing retinopathy. RESULTS: Statistically significant reduction in glucose, and elevation of protein content, SOD, CAT, and GSH levels and decreased levels of AR and PCO in lens homogenate and significant reduction in AGEs serum and lens homogenate were observed. Slit lamp examination, fundoscope, and histopathology showed improvement in retinal changes in APLC-treated rats compared to diabetic control animals. CONCLUSION: The treatment with APLC found to delay the progression of diabetic cataractogenesis and retinopathy, which might be due to its antioxidant activity, because of the presence of active phytochemicals in APLC.

Multi-targeting Andrographolide and its Natural Analogs as Potential Therapeutic Agents.

Andrographis paniculata (A. paniculata) is a medicinal plant used in the Indian and Chinese traditional medicinal systems for its various beneficial properties of therapeutics. This is due to the presence of a diterpene lactone called 'andrographolide'. Several biological activities like antiinflammatory, antitumour, anti-hyperglycaemic, anti-fertility, antiviral, cardio protective and hepatoprotective properties are attributed to andrographolide and its natural analogs. The studies have shown that not only this diterpene lactone (andrographolide), but also other related terpenoid analogs from A. paniculata could be exploited for disease prevention due to their structural similarity with diverse pharmacological activities. Several scientific groups are trying to unveil the underlying mechanisms involved in these biological actions brough aout by andrographolide and its analogs. This review aims at giving an overview on the therapeutical and/or pharmacological activities of andrographolide and its derivatives and also exemplify the underlying mechanisms involved.

Biological and Phytopharmacological Descriptions of Litchi Chinensis.

Plants remain a vital source of drugs and at present, much emphasis is given to nutraceuticals. Herbal medicines have been the basis of treatment and cure for various diseases and physiological conditions in the traditional methods practiced such as ayurveda and homeopathy. Litchi chinensis belongs to the Sapindaceae family and is well-known in the Indian traditional system for its traditional uses. The parts of the plant used are leaves, flowers, fruits, seed, pulp, and pericarp. All parts of the plant are rich sources of phytochemicals--epicatechin; procyanidin A2 and procyanidin B2; leucocyanidin; cyanidin glycoside, malvidin glycoside, and saponins; butylated hydroxytoluene; isolariciresinol; kaempferol; rutin; and stigmasterol. In the present review, we explore the lychee's description, traditional medicinal uses, and phytoconstituents, and investigate the pharmacological activities in various parts of the lychee to show its importance in ethanopharmacology. This is so that this review can serve as a ready-to-use material for further research on the plant.

Therapeutic Potentials of Triterpenes in Diabetes and its Associated Complications.

Diabetes is a major chronic metabolic disorder globally and around of 285 million people are affected by the disease and the number is expected to double in the next two decades. The major focus of anti-diabetic therapies is to enhance insulin production, sensitivity and/or reduce the blood glucose level. Although several synthetic drugs have been developed as antidiabetic agents but their utility has been hampered due to their side effects and poor efficacy. In this scenario, research on natural products has been gained importance due their safety profile in toxicity studies. Terpenoids belong to an important class of natural products and several terpenoids have been reported as antidiabetic agents. Some of them are under various stages of pre-clinical and clinical evaluation to develop them as antidiabetic agents. These agents can inhibit enzymes responsible for the development of insulin resistance, normalization of plasma glucose and insulin levels and glucose metabolism. Triterpenes can act as promising agents in the treatment of diabetic retinopathy, neuropathy and nephropathy or in impaired wound healing by inhibiting several pathways involved in the diabetes and associated complications. However, efforts in understanding the biological actions and clinical studies involving the applications of triterpenes in treating diabetes are very limited. Hence, special attention is imperative to explore the therapeutic potential of these compounds and provide new information to the scientific community. This review aims to provide the recent advances in triterpenes chemistry, its derivatives, biological interventions and its therapeutic applications with special emphasis on diabetes and its associated disorders.