Effect of Berberine on Glycation, Aldose Reductase Activity, and Oxidative Stress in the Lenses of Streptozotocin-Induced Diabetic Rats In Vivo-A Preliminary Study

Aldo-keto reductases: Role in cancer development and theranostics

Aldo-keto reductases (AKRs) are a superfamily of enzymes that play crucial roles in various cellular processes, including the metabolism of xenobiotics, steroids, and carbohydrates. A growing body of evidence has unveiled the involvement of AKRs in the development and progression of various cancers. AKRs are aberrantly expressed in a wide range of malignant tumors. Dysregulated expression of AKRs enables the acquisition of hallmark traits of cancer by activating oncogenic signaling pathways and contributing to chemoresistance. AKRs have emerged as promising oncotherapeutic targets given their pivotal role in cancer development and progression. Inhibition of aldose reductase (AR), either alone or in combination with chemotherapeutic drugs, has evolved as a pragmatic therapeutic option for cancer. Several classes of synthetic aldo-keto reductase (AKR) inhibitors have been developed as potential anticancer agents, some of which have shown promise in clinical trials. Many AKR inhibitors from natural sources also exhibit anticancer effects. Small molecule inhibitors targeting specific AKR isoforms have shown promise in preclinical studies. These inhibitors disrupt the activation of oncogenic signaling by modulating transcription factors and kinases and sensitizing cancer cells to chemotherapy. In this review, we discuss the physiological functions of human AKRs, the aberrant expression of AKRs in malignancies, the involvement of AKRs in the acquisition of cancer hallmarks, and the role of AKRs in oncogenic signaling, and drug resistance. Finally, the potential of aldose reductase inhibitors (ARIs) as anticancer drugs is summarized.

Berberine attenuates brain aging via stabilizing redox homeostasis and inflammation in an accelerated senescence model of Wistar rats

Aging is a multifaceted and progressive physiological change of the organism categorized by the accumulation of deteriorating processes, which ultimately compromise the biological functions. The objective of this study was to investigate the anti-aging potential of berberine (BBR) in D-galactose (D-Gal) induced aging in rat models. In this study, male Wistar rats were divided into four groups: The control group was given only vehicle, the BBR group was treated with berberine orally, the D-Gal group was treated with D-galactose subcutaneously and the BBR + D-Gal group was treated with D-galactose and berberine simultaneously. D-galactose exposure elevated the pro-oxidants such as malondialdehyde (MDA) level, protein carbonyl and advanced oxidation protein products (AOPP) in the brain. It decreased the anti-oxidants such as reduced glutathione (GSH) and ferric reducing antioxidant potential (FRAP) in the brain. D-galactose treatment also reduced the mitochondrial complexes (I, II, III and IV) activities and elevated the inflammatory markers such as interleukine-6 (IL-6), tumor necrosis factor- α (TNF-α) and C-reactive protein (CRP). The mRNA expressions of IL-6 and TNF-α in the brain were upregulated following D-galactose exposure. Berberine co-treatment in D-galactose induced aging rat model prevented the alteration of pro-oxidant and anti-oxidant in the brain. Berberine treatment restored the mitochondrial complex activities in the brain and also normalized the inflammatory markers. Based on these findings we conclude that berberine treatment has the potential to mitigate brain aging in rats via stabilizing the redox equilibrium and neuroinflammation.

Biologically active isoquinoline alkaloids covering 2019-2022

Isoquinoline alkaloids are an important class of natural products that are abundant in the plant kingdom and exhibit a wide range of structural diversity and biological activities. With the deepening of research in recent years, more and more isoquinoline alkaloids have been isolated and identified and proved to contain a variety of biological activities and pharmacological effects. In this review, we introduce the research progress of isoquinoline alkaloids from 2019 to 2022, mainly in the part of biological activities, including antitumor, antimicrobial, antidiabetic, antiviral, anti-inflammatory, antioxidant, neuroprotective, hepatoprotective, analgesic, and other activities. This study provides a clear direction for the rational development and utilization of isoquinoline alkaloids, suggesting that these alkaloids have great potential in the field of drug research.

Astragalin attenuates diabetic cataracts via inhibiting aldose reductase activity in rats

AIM

To investigate the aldose reductase (AR) inhibition capacity of astragalin (AST) against streptozoticin-induced diabetic cataracts (DCs) in rats.

METHODS

Ex vivo investigations were conducted by treating the lens of a goat placed for 72h in artificial aqueous humor (AAH) of pH 7.8 at room temperature with cataract-causing substance (55 mmol/L of galactose) and in vivo studies were performed on rats via induction with streptozotocin. AST was administered at different dose levels and scrutinize for DC activity.

RESULTS

In diabetic rats, AST improved the body weight, blood insulin, and glucose as well as the levels of galactitol in a dose-dependent way, other biochemical parameters i.e. inflammatory mediators and cytokines, and also suppress AR activity. The level of the antioxidant parameters such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activity were also altered on a diabetic lens after the administration of the AST.

CONCLUSION

AST protects against lens opacification to avoid cataracts and polyols formation, indicating that it could be used as a potential therapeutic agent for diabetes.

Berberine may provide redox homeostasis during aging in rats

Aging is a natural phenomenon, which is characterised by progressive physiological changes at cellular and organ level. During aging, the defence mechanism of an organism declines over the period of time. The aim of this study was to investigate the biological efficacy of berberine in D-galactose induced aging rat models. For the study, rats were divided into four groups: Control received only vehicle, BBR received berberine orally, D-Gal received D-galactose subcutaneously and BBR + D-Gal received D-galactose and berberine simultaneously. D-galactose treatment increased the pro-oxidants such as malondialdehyde (MDA) level, protein carbonyl, plasma membrane redox system (PMRS) and advanced oxidation protein products (AOPP) in the erythrocytes or plasma. It reduced the anti-oxidant level such as reduced glutathione (GSH), ferric reducing ability of plasma (FRAP), plasma thiols, sialic acid and membrane transporters like Na+/K+ ATPase and Ca2+ ATPase activity in the erythrocyte membrane. Co-treatment of berberine in D-galactose induced aging rat models restored pro-oxidants and anti-oxidants in erythrocytes. Berberine also restored the activity of Na+/K+ ATPase and Ca2+ ATPase in the erythrocyte membrane. On the basis of these findings, we suggest that berberine treatment could attenuate erythrocyte aging in rats through stabilisation of the redox equilibrium.

Current Approach to the Pathogenesis of Diabetic Cataracts

Cataracts remain the first or second leading cause of blindness in all world regions. In the diabetic population, cataracts not only have a 3–5 times higher incidence than in the healthy population but also affect people at a younger age. In patients with type 1 diabetes, cataracts occur on average 20 years earlier than in the non-diabetic population. In addition, the risk of developing cataracts increases with the duration of diabetes and poor metabolic control. A better understanding of the mechanisms leading to the formation of diabetic cataracts enables more effective treatment and a holistic approach to the patient.

A Review of Fibraurea tinctoria and Its Component, Berberine, as an Antidiabetic and Antioxidant

Diabetes mellitus is a group of metabolic disorders characterized by hyperglycemia caused by resistance to insulin action, inadequate insulin secretion, or excessive glucagon production. Numerous studies have linked diabetes mellitus and oxidative stress. People with diabetes usually exhibit high oxidative stress due to persistent and chronic hyperglycemia, which impairs the activity of the antioxidant defense system and promotes the formation of free radicals. Recently, several studies have focused on exploring natural antioxidants to improve diabetes mellitus. Fibraurea tinctoria has long been known as the native Borneo used in traditional medicine to treat diabetes. Taxonomically, this plant is part of the Menispermaceae family, widely known for producing various alkaloids. Among them are protoberberine alkaloids such as berberine. Berberine is an isoquinoline alkaloid with many pharmacological activities. Berberine is receiving considerable interest because of its antidiabetic and antioxidant activities, which are based on many biochemical pathways. Therefore, this review explores the pharmacological effects of Fibraurea tinctoria and its active constituent, berberine, against oxidative stress and diabetes, emphasizing its mechanistic aspects. This review also summarizes the pharmacokinetics and toxicity of berberine and in silico studies of berberine in several diseases and its protein targets.

Endophytes, a Potential Source of Bioactive Compounds to Curtail the Formation–Accumulation of Advanced Glycation End Products: A Review

Endophytes, microorganisms that live in the internal tissues and organs of the plants, are known to produce numerous bioactive compounds, including, at times, some phytochemicals of their host plant. For such reason, endophytes have been quoted as a potential source for discovering bioactive compounds, particularly, of medical interest. Currently, many non-communicable diseases are threatening global human health, noticeably: diabetes, neurodegenerative diseases, cancer, and other ailment related to chronic inflammation and ageing. Intriguingly, the pathogenesis and development of these diseases have been linked to an excessive formation and accumulation of advanced glycation end products (AGEs). AGEs are a heterogeneous group of compounds that can alter the conformation, function, and lifetime of proteins. Therefore, compounds that prevent the formation and consequent accumulation of AGEs (AntiAGEs compounds) could be useful to delay the progress of some chronic diseases, and/or harmful effects of undue AGEs accumulation. Despite the remarkable ability of endophytes to produce bioactive compounds, most of the natural antiAGEs compounds reported in the literature are derived from plants. Accordingly, this work covers 26 plant antiAGEs compounds and some derivatives that have been reported as endophytic metabolites, and discusses the importance, possible advantages, and challenges of using endophytes as a potential source of antiAGEs compounds.

Therapeutic Screening of Herbal Remedies for the Management of Diabetes

The study of diabetes mellitus (DM) patterns illustrates increasingly important facts. Most importantly, they include oxidative stress, inflammation, and cellular death. Up to now, there is a shortage of drug therapies for DM, and the discovery and the development of novel therapeutics for this disease are crucial. Medicinal plants are being used more and more as an alternative and natural cure for the disease. Consequently, the objective of this review was to examine the latest results on the effectiveness and protection of natural plants in the management of DM as adjuvant drugs for diabetes and its complex concomitant diseases.

Novel advances in inhibiting advanced glycation end product formation using natural compounds

Advanced glycation end products (AGEs) are a group of complex compounds generated by nonenzymatic interactions between proteins and reducing sugars or lipids. AGEs accumulate in vivo and activate various signaling pathways closely related to the occurrence of various chronic metabolic diseases. In this paper, we describe the process through which AGEs are formed, the classification of AGEs, and biological effects of AGEs on human health. Most importantly, we review recent progress in natural compound-based AGE formation inhibitors. Major classes of natural inhibitors, including polyphenols, polysaccharides, terpenoids, vitamins and alkaloids, have been described. Their mechanisms of action have been summarized as scavenging free radicals, chelating metal ions, capturing active carbonyl compounds, protecting protein glycation sites, and lowering blood glucose levels. Although these natural compounds have good antiglycation activity, to date, they are not widely used in the clinic, likely because of their low content levels. However, these natural compounds and their molecular frameworks will play a valuable role in inspiring drug discovery.

Delivery of Natural Agents by Means of Mesoporous Silica Nanospheres as a Promising Anticancer Strategy

Natural prodrugs derived from different natural origins (e.g., medicinal plants, microbes, animals) have a long history in traditional medicine. They exhibit a broad range of pharmacological activities, including anticancer effects in vitro and in vivo. They have potential as safe, cost-effective treatments with few side effects, but are lacking in solubility, bioavailability, specific targeting and have short half-lives. These are barriers to clinical application. Nanomedicine has the potential to offer solutions to circumvent these limitations and allow the use of natural pro-drugs in cancer therapy. Mesoporous silica nanoparticles (MSNs) of various morphology have attracted considerable attention in the search for targeted drug delivery systems. MSNs are characterized by chemical stability, easy synthesis and functionalization, large surface area, tunable pore sizes and volumes, good biocompatibility, controlled drug release under different conditions, and high drug-loading capacity, enabling multifunctional purposes. In vivo pre-clinical evaluations, a significant majority of results indicate the safety profile of MSNs if they are synthesized in an optimized way. Here, we present an overview of synthesis methods, possible surface functionalization, cellular uptake, biodistribution, toxicity, loading strategies, delivery designs with controlled release, and cancer targeting and discuss the future of anticancer nanotechnology-based natural prodrug delivery systems.