The Effect of Curcumin on Lipid Profile and Glycemic Status of Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

The effect of curcumin supplementation on glycemic indices in adults: A meta-analysis of meta-analyses

Curcumin, an inherent polyphenolic compound, has the potential to influence glycemic indices. Nevertheless, the conclusions drawn from extant meta-analyses remain contentious. To determine the impact of curcumin supplementation on these indices, the current umbrella meta-analysis included existing systematic reviews and meta-analyses. A thorough systematic search was conducted using databases Embase, PubMed, WOS, Scopus, and the Cochrane Library to acquire peer-reviewed literature published before January 2024. The random-effects model was employed to conduct a meta-analysis. The present analysis incorporated a total of 22 meta-analytic studies. The findings of our study indicate that the administration of curcumin supplements leads to a significant decrease in fasting blood sugar levels (FBS) (ES: -1.63; 95 % CI: -2.36, -0.89, P<0.001; I2=88.4 %, P<0.001), homeostasis model assessment-estimated insulin resistance (HOMA-IR) (ES: -0.38; 95 % CI: -0.48, -0.28, P<0.001; I2=35.9 %, P=0.142), hemoglobin A1c (HbA1c) (ES: -0.44; 95 % CI: -0.67, -0.21, P<0.001; I2=65.0 %, P=0.014), and insulin (ES: -0.86; 95 % CI: -1.52, -0.21, P=0.010; I2=92.5 %, P<0.001). The results of this study suggest that the administration of curcumin supplements may be a beneficial intervention for enhancing glycemic indices.

Herbal Products as Complementary or Alternative Medicine for the Management of Hyperglycemia and Dyslipidemia in Patients with Type 2 Diabetes: Current Evidence Based on Findings of Interventional Studies

Type 2 diabetes (T2D) is known as a major public health problem with a noticeable adverse impact on quality of life and health expenditures worldwide. Despite using routine multiple pharmacological and nonpharmacological interventions, including diet therapy and increasing physical activity, controlling this chronic disease remains a challenging issue, and therapeutic goals are often not achieved. Therefore, recently, other therapeutic procedures, such as using herbal products and functional foods as complementary or alternative medicine (CAM), have received great attention as a new approach to managing T2D complications, according to the literature. We reviewed the existing evidence that supports using various fundamental medicinal herbs, including cinnamon, saffron, ginger, jujube, turmeric, and barberry, as CAM adjunctive therapeutic strategies for T2D patients. The current review addressed different aspects of the potential impact of the abovementioned herbal products in improving glycemic indices and lipid profiles, including the effect size reported in the studies, their effective dose, possible side effects, herbs-drug interactions, and their potential action mechanisms.

Metabolic complications of psychotropic medications in psychiatric disorders: Emerging role of de novo lipogenesis and therapeutic consideration

Although significant advances have been made in understanding the patho-physiology of psychiatric disorders (PDs), therapeutic advances have not been very convincing. While psychotropic medications can reduce classical symptoms in patients with PDs, their long-term use has been reported to induce or exaggerate various pre-existing metabolic abnormalities including diabetes, obesity and non-alcoholic fatty liver disease (NAFLD). The mechanism(s) underlying these metabolic abnormalities is not clear; however, lipid/fatty acid accumulation due to enhanced de novo lipogenesis (DNL) has been shown to reduce membrane fluidity, increase oxidative stress and inflammation leading to the development of the aforementioned metabolic abnormalities. Intriguingly, emerging evidence suggest that DNL dysregulation and fatty acid accumulation could be the major mechanisms associated with the development of obesity, diabetes and NAFLD after long-term treatment with psychotropic medications in patients with PDs. In support of this, several adjunctive drugs comprising of anti-oxidants and anti-inflammatory agents, that are used in treating PDs in combination with psychotropic medications, have been shown to reduce insulin resistance and development of NAFLD. In conclusion, the above evidence suggests that DNL could be a potential pathological factor associated with various metabolic abnormalities, and a new avenue for translational research and therapeutic drug designing in PDs.

Is Curcumin Intake Really Effective for Chronic Inflammatory Metabolic Disease? A Review of Meta-Analyses of Randomized Controlled Trials

This review aimed to examine the effects of curcumin on chronic inflammatory metabolic disease by extensively evaluating meta-analyses of randomized controlled trials (RCTs). We performed a literature search of meta-analyses of RCTs published in English in PubMed®/MEDLINE up to 31 July 2023. We identified 54 meta-analyses of curcumin RCTs for inflammation, antioxidant, glucose control, lipids, anthropometric parameters, blood pressure, endothelial function, depression, and cognitive function. A reduction in C-reactive protein (CRP) levels was observed in seven of ten meta-analyses of RCTs. In five of eight meta-analyses, curcumin intake significantly lowered interleukin 6 (IL-6) levels. In six of nine meta-analyses, curcumin intake significantly lowered tumor necrosis factor α (TNF-α) levels. In five of six meta-analyses, curcumin intake significantly lowered malondialdehyde (MDA) levels. In 14 of 15 meta-analyses, curcumin intake significantly reduced fasting blood glucose (FBG) levels. In 12 of 12 meta-analyses, curcumin intake significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR). In seven of eight meta-analyses, curcumin intake significantly reduced glycated hemoglobin (HbA1c) levels. In eight of ten meta-analyses, curcumin intake significantly reduced insulin levels. In 14 of 19 meta-analyses, curcumin intake significantly reduced total cholesterol (TC) levels. Curcumin intake plays a protective effect on chronic inflammatory metabolic disease, possibly via improved levels of glucose homeostasis, MDA, TC, and inflammation (CRP, IL-6, TNF-α, and adiponectin). The safety and efficacy of curcumin as a natural product support the potential for the prevention and treatment of chronic inflammatory metabolic diseases.

Vitamin D Alleviates Type 2 Diabetes Mellitus by Mitigating Oxidative Stress-Induced Pancreatic β-Cell Impairment

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is a common metabolic disorder with rising incidence worldwide. This study explored the anti-T2DM role of vitamin D, thereby providing novel therapeutic strategies.

METHODS

C57BL/6 J mice and MIN6 cells were used to induce in vivo T2DM and damaged β-cell models, respectively. Body weights, fasting blood glucose, and fasting insulin were measured in mice. Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were conducted on mice. Lipid indices (TG, TC, LDL-C, and HDL-C) were detected in mouse serum. Hematoxylin-eosin staining was used to evaluate pancreatic tissue injury. ELISA was used to assess insulin and oxidative stress (OS) markers (MDA, GSH, and SOD) in mice and MIN6 cells. Production of ROS was detected in islet β-cells and MIN6 cells. Cell viability and apoptosis were evaluated using CCK-8 and flow cytometry, respectively. QRT-PCR and western blotting were used to detect pro-inflammatory factors (TNF-α and IL-6) and endoplasmic reticulum stress (ERS) markers (CHOP and GRP78), respectively.

RESULTS

Vitamin D reduced body weights, fasting blood glucose, and insulin and ameliorated glucose tolerance and insulin sensitivity in T2DM mice. Besides, vitamin D decreased serum TG, TC, LDL-C, and increased HDL-C in T2DM mice. Vitamin D inhibited pancreatic histopathological injury, cell apoptosis, OS, and β-cell decline in T2DM mice. Moreover, vitamin D alleviated cell death, insufficient insulin secretion, inflammation, OS, and ERS in damaged MIN6 cells. Notably, N-acetyl-L-cysteine (an OS inhibitor) enhanced these effects of vitamin D.

CONCLUSIONS

Vitamin D relieved T2DM symptoms by alleviating OS-induced β-cell impairment.

Effects of turmeric (Curcuma longa) supplementation on glucose metabolism in diabetes mellitus and metabolic syndrome: An umbrella review and updated meta-analysis

AIMS

This study aims to comprehensively review the existing evidence and conduct analysis of updated randomized controlled trials (RCTs) of turmeric (Curcuma longa, CL) and its related bioactive compounds on glycemic and metabolic parameters in patients with type 2 diabetes (T2DM), prediabetes, and metabolic syndrome (MetS) together with a sub-group analysis of different CL preparation forms.

METHODS

An umbrella review (UR) and updated systematic reviews and meta-analyses (SRMAs) were conducted to evaluate the effects of CL compared with a placebo/standard treatment in adult T2DM, prediabetes, and MetS. The MEDLINE, Embase, The Cochrane Central Register of Control Trials, and Scopus databases were searched from inception to September 2022. The primary efficacy outcomes were hemoglobin A1C (HbA1C) and fasting blood glucose (FBG). The corrected covered area (CCA) was used to assess overlap. Mean differences were pooled across individual RCTs using a random-effects model. Subgroup and sensitivity analyses were performed for various CL preparation forms.

RESULTS

Fourteen SRMAs of 61 individual RCTs were included in the UR. The updated SRMA included 28 studies. The CCA was 11.54%, indicating high overlap across SRMAs. The updated SRMA revealed significant reduction in FBG and HbA1C with CL supplementation, obtaining a mean difference (95% confidence interval [CI]) of -8.129 (-12.175, -4.084) mg/dL and -0.134 (-0.304, -0.037) %, respectively. FBG and HbA1C levels decreased with all CL preparation forms as did other metabolic parameters levels. The results of the sensitivity and subgroup analyses were consistent with those of the main analysis.

CONCLUSION

CL supplementation can significantly reduce FBG and HbA1C levels and other metabolic parameters in T2DM and mitigate related conditions, including prediabetes and MetS.

TRIAL REGISTRATION

PROSPERO (CRD42016042131).

Overview of Curcumin and Piperine Effects on Glucose Metabolism: The Case of an Insulinoma Patient’s Loss of Consciousness

The hypoglycemic properties of curcumin supplements in therapeutic doses are well-known and may represent a useful tool for the treatment of chronic diseases such as metabolic syndrome, insulin resistance and type 2 diabetes. The poor bioavailability of curcumin can be improved with the concomitant administration of piperine, with no severe adverse effects on glycemia reported so far in the literature. In this article, we further discuss a previously reported case of a helicopter pilot, affected by grade I obesity who, under curcumin and piperine treatment, experienced a transient loss of consciousness (TLOC), during a low-altitude flight. This episode led to a diagnosis of insulinoma, previously asymptomatic. We hypothesized that the combined effects of curcumin and piperine might have caused a severe hypoglycemic episode and subsequent TLOC. Therefore, further studies should be conducted to evaluate the safety of curcumin and piperine supplementation in subjects with impaired glucose metabolism and insulin secretion.

Microencapsulated curcumin from Curcuma longa modulates diet-induced hypercholesterolemia in Sprague Dawley rats

Hypercholesterolemia is one of the major causes of cardiovascular ailments. The study has been conducted on the hypothesis that hypercholesterolemia can be modulated by microencapsulated curcumin due to its enhanced bioavailability. In this context, curcumin obtained from fresh rhizomes of Curcuma longa by conventional (CSE) and supercritical fluid (SFE) extractions, has been successfully microencapsulated using a mixture of gelatin and maltodextrin. The microencapsulated curcumin _CSE&SFE, has been added as supplemented diet and has been resulted in maximum plasma concentration of curcumin at 100 min as 529.31 ± 8.73 and 405.23 ± 7.12 μg/mL, respectively compared to non-encapsulated turmeric powder used as control. During the bio evaluation trial, turmeric powder (3%), microencapsulated curcumin_CSE (1%) and microencapsulated curcumin_SFE (0.5%) were provided to designate rat groups categorized by normal; N₁, N₂, and N₃ and hypercholesterolemic; H₁, H₂, and H₃ conditions, respectively. The incorporation of microencapsulated curcumin_SFE in the supplemented diet caused a reduction in serum cholesterol, low density lipoprotein (LDL) and triglycerides, athrogenic index (AI) and cardiac risk ration (CRR) as 5.42 and 12.81%, 7.25 and 15.42%, 3.17 and 9.38%, 15.38 and 29.28%, and 10.98 19.38% in normo- and hypercholesterolemic rat groups. Additionally, high-density lipoprotein (HDL) and anti-atherogenic index (AAI) indicated a significant increase in all treated rat groups. Conclusively, the inclusion of turmeric and curcumin microencapsulates in the dietary module has been proven effective to alleviate hyperlipidemia. Therefore, the present study is proven that curcumin absorption via the gastrointestinal tract and its stability toward metabolization in the body increased via microencapsulation using maltodextrin and gelatin. Microencapsulated curcumin reaches the target site via oral administration because of sufficient gastrointestinal residence period and stability in the digestive tract.

Curcumin and Capsaicin-Loaded Ag-Modified Mesoporous Silica Carriers: A New Alternative in Skin Treatment

Biologically active substances of natural origin offer a promising alternative in skin disease treatment in comparison to synthetic medications. The limiting factors for the efficient application of natural compounds, such as low water solubility and low bioavailability, can be easily overcome by the development of suitable delivery systems. In this study, the exchange with the template procedure was used for the preparation ofa spherical silver-modified mesoporous silica nanocarrier. The initial and drug-loaded formulations are fully characterized by different physico-chemical methods. The incipient wetness impregnation method used to load health-promoting agents, curcumin, and capsaicin in Ag-modified carriers separately or in combinationresulted in high loading efficiency (up to 33 wt.%). The interaction between drugs and carriers was studied by ATR-FTIR spectroscopy. The release experiments of both active substances from the developed formulations were studied in buffers with pH 5.5, and showed improved solubility. Radical scavenging activity and ferric-reducing antioxidant power assays were successfully used for the evaluation of the antiradical and antioxidant capacity of the curcumin or/and capsaicin loaded on mesoporous carriers. Formulations containing a mixture of curcumin and capsaicin were characterized bypotentiation of their antiproliferative effect against maligning cells, and it was confirmed that the system for simultaneous delivery of both drugs has lower IC50 values than the free substances.The antibacterial tests showed better activity of the obtained delivery systems in comparison with the pure curcumin and capsaicin. Considering the obtained results, it can be concluded that the obtained delivery systems are promising for potential dermal treatment.