Role of curcumin in ameliorating hypertension and associated conditions: a mechanistic insight

Protective Effects of Isolated Curcumin From Curcuma longa on Key Enzymes Involved in the Insulin Signaling Pathway and Digestive and Metabolic Enzymes Associated With Obesity, Type 2 Diabetes, and Hypertension

This study explores the potential of curcumin (CUR), extracted from Curcuma longa, in combating obesity and Type 2 diabetes. Obesity and Type 2 diabetes were induced in rats through a high-fat and high-fructose diet (HFFD), and CUR, after purification and characterization by Fourier transform infrared spectroscopy (FTIR) and ultraviolet (UV) spectroscopy, was administered for 3 months via gastric gavage. The results show that CUR supplementation activates the insulin signaling pathway in a dose-dependent manner, leading to improved insulin sensitivity. Specifically, administering CUR at a daily dose of 100 mg/kg significantly reduces the activities of protein tyrosine phosphatase (PTP1B) and dipeptidyl peptidase-4 (DPP-4) by 43% and 45%, respectively, in obese and Type 2 diabetic rats compared to untreated obese rats. Furthermore, CUR effectively inhibits lipase and α-amylase activities at both the serum and intestinal levels. In obese rats, CUR administration reduces glycogen phosphorylase (GP) activity by 35% and enhances glycogen synthase (GS) activity by 78%, leading to a substantial increase in hepatic glycogen content. Additionally, CUR also led to a 21% reduction in food intake and a 12% decrease in water consumption. These changes contributed to significant reductions in the blood sugar and glycosylated hemoglobin (HbA1c) levels, with decreases of 59% and 53%, respectively. Additionally, administering CUR at a dose of 100 mg/kg body weight reduced thiobarbituric acid reactive substances (TBARSs), hydrogen peroxide (H2O2), and total oxidant status (TOS) in obese and diabetic rats, with reductions of 49%, 59%, and 58%, respectively. Furthermore, CUR demonstrates a strong regulatory effect on the levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and total cholesterol (TC). Overall, these results underscore the CUR potential for treating and preventing diabetes and obesity.

Therapeutic Potential of Hexahydrocurcumin in the Regeneration and Protection of the Retinal Pigment Epithelium

Hexahydrocurcumin (HHC), the primary metabolite of curcumin, shows promising therapeutic potential due to its antioxidant and anti-inflammatory properties. The retinal pigment epithelium (RPE) plays a crucial role in maintaining retinal homeostasis; however, its dysfunction-linked to oxidative stress and chronic inflammation-contributes to the progression of degenerative diseases such as age-related macular degeneration (AMD). This review highlights the therapeutic potential of HHC in protecting and regenerating RPE cells. It explores the effects of oxidative stress on the RPE, the mechanisms underlying its damage, and the involvement of reactive oxygen species (ROS) and inflammatory mediators. HHC has demonstrated the ability to modulate these pathways by activating nuclear factor erythroid 2-related factor 2 (NRF2), enhancing antioxidant defenses, and inhibiting pro-inflammatory cytokine production. Preclinical studies suggest that HHC mitigates vascular remodeling and endothelial dysfunction by reducing the expression of transforming growth factor β (TGF-β1) and matrix metalloproteinase-9 (MMP-9). Moreover, HHC improves nitric oxide bioavailability and promotes nitric oxide synthase expression, thereby counteracting oxidative stress-induced vascular damage. Emerging evidence indicates that HHC may be a promising candidate for the treatment of retinal degenerative diseases, particularly those associated with oxidative stress and inflammation. However, further studies, including clinical trials, are essential to confirm its efficacy and elucidate the precise mechanisms underlying HHC's protective effects on RPE cells.

Repurposing of phosphodiesterase-5 inhibitor sildenafil as a therapeutic agent to prevent gastric cancer growth through suppressing c-MYC stability for IL-6 transcription

Phosphodiesterase-5 (PDE5) inhibitors have shown promise as anti-cancer agents in malignancies. However, their specific effects on gastric cancer (GC) and the underlying mechanisms remain elusive. Our aim was to investigate this by combining evidence from population-based studies with data obtained from in vivo and in vitro experiments. By combing a couple of nationwide Swedish registers, GC patients who received PDE5 inhibitors were compared to matched controls while adjusting for confounding factors. The anti-tumor effect and mechanism of the PDE5 inhibitor sildenafil were evaluated via using tumor cells, patient-derived tumor organoids and xenograft animal models in GC. A total of 161 Swedish GC patients from a nationwide population-based cohort who received post-diagnostic PDE5 inhibitors demonstrated lower cancer-specific mortality compared to the controls (HR = 0.66, 95% CI = 0.47-0.92, P = 0.016). Functionally, the PDE5 inhibitor sildenafil exhibited the suppressive ability to prevent oncogenic growth in GC. Mechanistically, sildenafil restrained GC growth by directly activating PKG through PDE5 inhibition for regulating c-MYC expression via its phosphorylation and ubiquitination degradation, thereby suppressing c-MYC stability for IL-6 transcription within the downstream IL-6/JAK/STAT3 signalling pathway. The PDE5 inhibitor sildenafil may serve as a promising adjuvant for GC therapy if further randomized clinical trials confirm its efficacy.

Bioactive Macromolecule-mediated Biogenic FeONPs Attenuate Inflammation in Atherosclerotic Rat by Activating PI3K/Akt/eNOS Pathway

INTRODUCTION

Atherosclerosis refers to the thickening and hardening of artery walls. In our latest experiment, we utilized environmentally friendly techniques to produce multifunctional iron oxide nanoparticles (FeONPs) aimed at reducing inflammation in rats with atherosclerosis.

METHODS

The formulation was synthesized using curcumin (as the potent bioactive molecule) and was characterized. We assessed the in vitro antioxidant capability of the formulation against DPPH free radicals. Additionally, we quantified the mRNA levels of eNOS, PI3K, and Akt using Real Time-Polymerase Chain Reaction (RT-PCR). We tested the therapeutic impact of the bioactive formulation on a Triton X-100-induced atherosclerosis mouse model.

RESULTS

The crystallinity and magnetic behavior confirmed the magnetic properties of the FeONPs. The DPPH assay exhibited the dose-dependent radical scavenging characteristics of FeONPs. In the animal experiments, significant upregulation of the studied genes was noticed in treated groups 2 and 3 compared to treated group 1. Moreover, the expression of PI3K/eNOS/Akt was greater in treated group 3 than in treated group 2. These results indicate a dose-dependent elevation in target gene expression.

CONCLUSION

Nevertheless, the variation in gene expression between the negative control and the untreated control was not statistically significant (p > 0.05) across all genes.

Synergistic effects of curcumin and stem cells on spinal cord injury: a comprehensive review

Spinal cord injury (SCI) is damage to the spinal cord that permanently or temporarily disrupts its function, causing considerable autonomic, sensory, and motor disorders, and involves between 10 and 83 cases per million yearly. Traumatic SCI happens following primary acute mechanical damage, leading to injury to the spinal cord tissue and worsening clinical outcomes. The present therapeutic strategies for this complex disease fundamentally rely on surgical approaches and conservative remedies. However, these modalities are not effective enough for neurological recovery. Therefore, it is necessary to discover more efficient methods to treat patients with SCI. Today, considerable attention has been drawn to bioactive compounds-based remedies and stem cell therapy for curing various ailments and disorders, such as neurological diseases. Some researchers have recommended that harnessing curcumin, a polyphenol obtained from turmeric, in combination with stem cells, like mesenchymal stem cells, neural stem cells, and ependymal stem cells, can remarkably improve neurological recovery-related parameters more effective than the treatment with these two methods separately in experimental models. Hereby, this literature review delves into the functionality of curcumin combined with stem cells in treating SCI with a focus on cellular and molecular mechanisms.

Recent updates on clinical developments of curcumin and its derivatives

Curcumin, a natural polyphenol, derived from Curcuma longa L. is extensively studied by various researchers across the globe and has established its immense potential in the management of several disorders at clinical level. The underlying mechanism of curcumin involves regulation of various molecular targets, namely, inflammatory cytokines, transcription factor, apoptotic genes, growth factors, oxidative stress biomarkers, and protein kinases. In clinical trials, curcumin as an adjuvant has significantly boost-up the efficacy of many proven drugs in the management of arthritis, neurodegenerative disorder, oral infection, and gastrointestinal disorders. Moreover, clinical studies have suggested curcumin as an appropriate candidate for the prevention and/or management of various cancers via regulation of signaling molecules including NF-kB, cytokines, C-reactive protein, prostaglandin E2, Nrf2, HO-1, ALT, AST, kinases, and blood profiles. This article highlights plethora of clinical trials that have been conducted on curcumin and its derivatives in the management of several ailments. Besides, it provides recent updates to the investigators for conducting future research to fulfill the current gaps to expedite the curcumin utility in clinical subjects bearing different pathological states.

Curcumin derived from medicinal homologous foods: its main signals in immunoregulation of oxidative stress, inflammation, and apoptosis

It has been for thousands of years in China known medicinal homologous foods that can be employed both as foods and medicines to benefit human and animal health. These edible herbal materials perform divert roles in the regulation of metabolic disorders, cancers, and immune-related diseases. Curcumin, the primary component derived from medicinal homologous foods like curcuma longa rhizome, is reported to play vital actions in organic activities, such as the numerous pharmacological functions including anti-oxidative stress, anti-inflammation and anti/pro-apoptosis in treating various diseases. However, the potential mechanisms of curcumin-derived modulation still need to be developed and attract more attention worldwide. Given that these signal pathways are enrolled in important bioactive reactions, we collected curcumin's last achievements predominantly on the immune-regulation signals with the underlying targetable strategies in the last 10 years. This mini-review will be helpful to accelerate curcumin and other extracts from medicinal homologous foods use in future human clinical applications.

Bioactive compounds in childhood obesity and associated metabolic complications: Current evidence, controversies and perspectives

Obesity represents the most frequent chronic disease among children worldwide, with a significant global burden on society. Metabolically unhealthy obesity (MUO) can affect children since their first years of life, and novel therapeutic strategies to tackle metabolic complications are under investigation. This review focuses on bioactive compounds and their possible beneficial effects on obesity, particularly omega-3, docosahexaenoic acid, vitamin D, biotics, polysaccharide macromolecules, polyphenols, inositols, alpha lipoic acid, and bromelaine. Our aim is to summarize current evidence about bioactive compounds in the treatment of obesity, highlighting recent findings on their use in children and adolescents. Most studied molecules are omega-3 and vitamin D, despite the heterogeneity between the studies. Moreover, given the emerging interest in the gut-brain axis in the link between metabolic health and microbiota, various studies on prebiotics, probiotics, synbiotics, postbiotics and polysaccharide macromolecules have been considered. Some preclinical studies seem to highlight a possible role of the polyphenols, even if their clinical evidence is still discussed. Lastly, we describe possible effects of inositols and alpha-lipoic acid. Despite some dietary supplements seem to be promising in overweight subjects, only in a few of them a dose/response efficacy has been found in the pediatric age. Innovative, well-designed and targeted clinical trials are then needed to prove the beneficial effects of these compounds that could support the standard behavioral therapy for obesity.

Sepsis-induced AKI: From pathogenesis to therapeutic approaches

Sepsis is a heterogenous and highly complex clinical syndrome, which is caused by infectious or noninfectious factors. Acute kidney injury (AKI) is one of the most common and severe complication of sepsis, and it is associated with high mortality and poor outcomes. Recent evidence has identified that autophagy participates in the pathophysiology of sepsis-associated AKI. Despite the use of antibiotics, the mortality rate is still at an extremely high level in patients with sepsis. Besides traditional treatments, many natural products, including phytochemicals and their derivatives, are proved to exert protective effects through multiple mechanisms, such as regulation of autophagy, inhibition of inflammation, fibrosis, and apoptosis, etc. Accumulating evidence has also shown that many pharmacological inhibitors might have potential therapeutic effects in sepsis-induced AKI. Hence, understanding the pathophysiology of sepsis-induced AKI may help to develop novel therapeutics to attenuate the complications of sepsis and lower the mortality rate. This review updates the recent progress of underlying pathophysiological mechanisms of sepsis-associated AKI, focuses specifically on autophagy, and summarizes the potential therapeutic effects of phytochemicals and pharmacological inhibitors.