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).

Anti-hypotensive effect of "Yahom Navakot" in rats with orthostatic hypotension.

Background and aim: Yahom Navakot (YN), is a Thai traditional medicine, consisting of 54 plants, for treating fainting and dizziness. Thus, YN might relieve orthostatic hypotension (OH) symptoms, but its therapeutic action is unclear. Therefore, this study evaluated YN in OH rats, using a head-up tilt test (HUT). Experimental procedure: Rats were anesthetized, and OH induced via a 90oHUT, before and after administering vehicle, a YN powder suspension (10, 100 mg/kg), a YN aqueous extract (100 mg/kg), and midodrine (5 mg/kg). The systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), pulse pressure (PP) and heart rate (HR) were determined via the carotid artery. Plasma noradrenaline (NA) was evaluated. YN-induced vasoconstriction of isolated rat aorta rings was determined using organ bath technique. Results and conclusion: Baseline BP increased with the 100 mg/kg YN powder suspension, the YN aqueous extract or midodrine, while HR decreased, compared with vehicle and control. 90oHUT rapidly reduced SBP, DPB and MAP, but increased HR, for control and vehicle-treated groups, but BP was steady with the 100 mg/kg YN powder suspension, the YN aqueous extract or midodrine. The 90oHUT-increase in HR was most pronounced with the 100 mg/kg YN powder suspension (the traditional formulation). This accords with increased plasma NA. YN also induced vasoconstriction in rat aorta via α1-receptor activation. Thus, the anti-hypotensive action of YN involved a stimulating effect on the heart and blood vessels via sympathetic activation. The results support the traditional use of YN and demonstrated the effectiveness of YN for OH prevention.

The effect of Cissus quadrangularis L. on delaying bone loss in postmenopausal women with osteopenia: A randomized placebo-controlled trial.

BACKGROUND: Osteopenia refers to bone density that is not normal but also not as low as that noted in osteoporosis. Osteopenia leads to osteoporosis and increases the risk of fractures. Current research is focused on agents that will prevent or slow the progression of bone loss. On the basis of published evidence, Cissus quadrangularis (CQ) might potentially provide a novel natural treatment for osteopenia. PURPOSE: To determine the effect of 24 weeks of consecutive treatment with CQ on delaying bone loss and safety in postmenopausal women (PMW) with osteopenia. METHODS: This study is a randomized, placebo-controlled trial. Here, 134 enrolled PMW with osteopenia (> 40 years and having no period for 1-10 years) received CQ at 1.2 (CQ1.2) or 1.6 g/day (CQ1.6) or placebo. The %change in bone mineral density (BMD) at the lumbar spine (L1-L4), femoral neck, and total hip served as the primary outcome. The %change in bone turnover markers (BTMs), including C-terminal telopeptide of type 1 collagen (CTX) and procollagen type 1 amino-terminal propeptide (P1NP), was the secondary outcome. These outcomes were compared between the CQ vs. placebo group at weeks 12 and 24. The least significant change (LSC) was used to monitor clinical changes. The adverse events (AE) were monitored. RESULTS: A total of 108 participants completed this study. The %BMD changes in the CQ-treated groups did not differ at any site after 24 weeks compared to the placebo. Statistically significant differences were detected in CQ1.6 at the lumbar spine (0.011 ± 0.025 g/cm2, p = 0.008) and CQ1.2 at the femoral neck (-0.015 ± 0.036 g/cm2, p = 0.024) compared to baseline, but these changes did not exceed the LSC. Reduced bone remodeling activity was detected in both CQ-treated groups. Compared to the placebo, the %P1NP change was significantly reduced in CQ1.6 (-2.46 ± 26.05%; p < 0.01) at week 12 and in CQ1.2 (-3.36 ± 29.47%; p < 0.01) and CQ1.6 (-9.95 ± 22.22%; p < 0.01) at week 24. These results correlated with the within-group comparison, which showed a continuously significant increase in both BTMs in the placebo group. However, a stable CTX and a significant reduction in P1NP (p < 0.05) were detected in both CQ-treated groups. This reduction exceeded the LSC of P1NP. The incidence of adverse events did not differ among the three groups. CONCLUSION: This is the first clinical report that showed a promising effect on delaying bone loss of orally administration of CQ for 24 weeks, as indicated by a slower bone remodeling process via a reduction in BTMs. However, no change in BMD was observed.

Green extraction optimization of triterpenoid glycoside-enriched extract from Centella asiatica (L.) Urban using response surface methodology (RSM).

Centella asiatica (L.) Urban extracts are widely used as food, drugs and cosmetics, and the main active compounds are glycosides (madecassoside and asiaticoside) and aglycones (madecassic acid and asiatic acid). Green extraction is an interesting concept that can produce safe and high-quality extracts that use less solvent, time and energy with the environmental friendly. This study investigated the optimum conditions for extracting a triterpenoid glycoside-enriched C. asiatica extract using microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE). Central composite design and response surface methodology (RSM) were used for the experimental design and data analysis. Four-month-old C. asiatica tetraploid plants were selected as the elite raw material containing high amount of triterpenoid glycosides for the extraction experiments, and the triterpenoid content was determined by a validated HPLC method. The results demonstrated that the RSM models and equations were reliable and could predict the optimal conditions to enhance C. asiatica extract yield, glycoside and aglycone amounts. The percent of ethanol was the major factor that had a significant effect on C. asiatica yield and glycoside and aglycone content during MAE and UAE. The maximum triterpenoids content in extract; 7.332 ± 0.386% w/w madecassoside and 4.560 ± 0.153% w/w asiaticoside 0.357 ± 0.013% w/w madecassic acid and 0.209 ± 0.025% w/w asiatic acid were obtained by MAE with 80% ethanol at 100 watts for 7.5 min, whereas the optimal conditions for highest total triterpenoids extraction from dry plant was UAE with 80% ethanol, temperature 48 °C, 50 min enhanced 2.262 ± 0.046% w/w madecassoside, 1.325 ± 0.062% w/w asiaticoside, 0.082 ± 0.009% w/w madecassic acid and 0.052 ± 0.007% w/w asiatic acid as secondary outcome. Moreover, it was found that MAE and UAE consumed energy 59 and 54%, respectively, lower than that of the conventional method, maceration, in term of kilowatt-hour per gram of total triterpenoids. These optimized green conditions could be recommended for C. asiatica extraction for triterpenoid glycoside-enriched extracts production for the pharmaceutical or cosmeceutical industries and triterpenoids quantitative analysis in raw materials.

Effect of tomato, lycopene and related products on blood pressure: A systematic review and network meta-analysis.

BACKGROUND: A number of randomized controlled trials (RCTs) have been conducted to evaluate the hypotensive effects of tomato, lycopene, and related products. However, the findings were conflicting, partly due to differences in the types of products investigated. Therefore, this study aimed to assess and compare the hypotensive effects of different tomato-related preparations through a network meta-analysis based on randomized controlled trials. STUDY DESIGN: A systematic review and network meta-analysis. METHODS: A network meta-analysis based on a systematic review of RCTs comparing the effect of various tomato, lycopene and related products versus placebo on blood pressure in adults was performed. PubMed, EMBASE, SCOPUS, and Clinicaltrial.gov databases were searched up to October 2020 without language restrictions. The primary outcomes were systolic and diastolic blood pressure. Mean differences (MDs) along with 95% confidence intervals (CIs) were estimated and pooled using a random-effects model. Heterogeneity was assessed using the global inconsistency test. RESULTS: A total of 11 studies including six forms of tomato, lycopene and related products met the inclusion criteria. Among these trials, eight (N = 617) and seven trials (N = 501) were included in the analysis of systolic (SBP) and diastolic blood pressure (DBP) outcomes, respectively. The standardized tomato extract (STE) significantly decreased SBP compared to placebo, with a pooled MD (95% CI) of -5.89 (-9.13 to -2.64) mmHg. The effect on DBP was not significant, with a pooled MD (95% CI) of -3.51 (-7.39 to 0.38) mmHg. Subgroup analysis in hypertensive patients showed that STE significantly reduced both SBP and DBP with pooled MDs (95% CIs) of -8.09 (-11.52 to -4.67) and -4.25 (-6.97 to -1.53) mmHg, respectively, compared to placebo. Other forms of tomato, including other dose ranges of standardized tomato extract, tomato-containing diet, lycopene-free preparation, and synthetic lycopene, did not show consistent and significant effects on either SBP or DBP in all analyses. CONCLUSION: Standardized tomato extract (STE) significantly decreased SBP compared to placebo in a mixed population of healthy volunteers and hypertensive patients. The BP-lowering effect was more pronounced among hypertensive patients. No significant BP effects were seen with other forms of tomato, lycopene and related products in the overall population or any subgroup of the population.

Effects of methyl jasmonate on the growth and triterpenoid production of diploid and tetraploid Centella asiatica (L.) Urb. hairy root cultures.

In this study, the effects of methyl jasmonate (MeJA) on the phytomass and triterpenoid production of diploid and tetraploid Centella asiatica hairy roots were investigated. Hairy root cultures were obtained from diploid and induced tetraploid plants of C. asiatica infected by Agrobacterium rhizogenes strain ATCC 43057. MeJA triggered triterpenoid production in both ploidy hairy roots, whereas triterpenoids were not produced in the untreated hairy roots. Among the treatments, the 50 µM MeJA treatment yielded the maximum triterpenoid production in diploid hairy roots of 27.25 ± 0.27 µg/mg Dry weight (DW) total triterpenoid at day 21. For the tetraploid hairy root cultures, the 28th-day hairy root culture produced a maximum amount of triterpenoids of 16.29 ± 6.32 µg/mg DW in response to the 50 µM MeJA treatment, whereas the 100 µM MeJA treatment produced a similar triterpenoid amount (16.31 ± 9.24 µg/mg DW) at day 14. Moreover, in response to 50 µM MeJA, we obtained different ratios of aglycone to glycoside, i.e., 1:7 and 1:2, between the diploid and tetraploid hairy root cultures. Asiaticoside was the dominant phytochemical, followed by asiatic acid and madecassic acid. This study provides valuable information for producing triterpenoids for C. asiatica commercial products and preparations by using hairy root cultures.

Alkaline phosphatase activity-guided isolation of active compounds and new dammarane-type triterpenes from Cissus quadrangularis hexane extract.

ETHNOPHARMACOLOGICAL RELEVANCE: The stem of Cissus quadrangularis L. (CQ) is used in traditional medicine to treat bone fractures and swelling. Anti-osteoporotic activity of CQ hexane extract has been reported, but the active compounds in this extract remain unknown. Thus, we aimed to identify the active compounds in CQ hexane extract using bioassay-guided isolation. MATERIALS AND METHODS: The CQ hexane extract was fractionated sequentially with benzene, dichloromethane, ethyl acetate, and methanol. The examination of CQ extract and its fractions was guided by bioassays for alkaline phosphatase (ALP) activity during the differentiation of MC3T3-E1 osteoblastic cells. The cells were treated with or without the CQ extract and its fractions for a period of time, and then the stimulatory effect of the alkaline phosphatase enzyme, a bone differentiation marker, was investigated. The compounds obtained were structurally elucidated using spectroscopic techniques and re-evaluated for activity during bone differentiation. RESULTS: A total of 29 compounds were isolated, viz., triterpenes, fatty acid methyl esters, glycerolipids, steroids, phytols, and cerebrosides. Four new dammarane-type triterpenes were isolated for the first time from nature, and this report is the first to identify this group of compounds from the Vitaceae family. Seven compounds, viz., glycerolipids and squalene, stimulated ALP activity at a dose of 10µg/mL. Moreover, the synergistic effect of these compounds on bone formation was demonstrated. CONCLUSION: This report describes, for the first time, the isolation of active compounds from CQ hexane extract; these active compounds will be useful for the quality control of extracts from this plant used to treat osteoporosis.