Context: Chatuphalatika (CTPT), is a Thai herbal formulation mixture of Phyllanthus emblica Linn. (Euphorbiaceae), Terminalia belerica Linn. (Combretaceae), T. chebula and the fruit of T. arjuna (Roxb.) Wight & Arn. CTPT is considered to exert anti-inflammatory and antihyperuricemic effects, but there have been no reports to demonstrate these pharmacological effects in a quantitative manner. Objectives: To investigate the antioxidative, anti-inflammatory and antihyperuricemic effects of CTPT. Materials and methods: Antioxidant activities of CTPT extracts were measured in vitro by DPPH, ABTS and FRAP assays, and anti-inflammatory effect by measuring inflammatory mediator production induced by lipopolysaccharide (LPS) in RAW264.7 macrophages. The mechanism of the hypouricemic effect was investigated using oxonate-induced hyperuricemic ddY mice treated with oral administrations of CTPT at 250, 500 and 1000 mg/kg. Results: Antioxidant activities of CTPT measured by ABTS and FRAP assays were 1.35 g TEAC/g extract and 10.3 mmol/100 g extract, respectively. IC₅₀ for the inhibition of DPPH radical was 13.8 µg/mL. CTPT (10 µg/mL) significantly downregulated the mRNA expression of TNF-α and iNOS in RAW 264.7 cells. Lineweaver–Burk analysis of the enzyme kinetics showed that CTPT inhibited xanthine oxidase (XOD) activity in a noncompetitive manner with the K_i of 576.9 µg/mL. Oral administration of CTPT (1000 mg/kg) significantly suppressed uric acid production by inhibiting hepatic XOD activity, and decreased plasma uric acid levels in hyperuricemic mice by approximately 40% (p < 0.05). Conclusions: This study demonstrated for the first time the antioxidative, anti-inflammatory and antihyperuricemic effects of CTPT in vivo and in vitro, suggesting a possibility of using CTPT for the treatment of hyperuricemia in gout.

Lysiphyllum strychnifolium (Craib) A. Schmitz (LS) (Fabaceae) has traditionally been used to treat diabetes mellitus.This study demonstrates the antidiabetic and antioxidant effects of aqueous extr...

Maclura cochinchinensis (MC) (Lour.) heartwood extract have been used traditionally to treat diabetes in Thailand, but their mechanism of action has not been elucidated. This study investigated the effects of an aqueous heartwood extract of MC on α-glucosidase and α-amylase activities. Moreover, its antidiabetic effect was evaluated using an oral glucose tolerance test (OGTT) and a 28-day administration to streptozotocin (STZ)-nicotinamide (NA)-induced type 2 diabetic mice. In both OGTT and the daily oral administration for 28 days in STZ-NA-induced type 2 diabetic mice models, the extract (1,000 mg/kg) significantly decreased fasting blood glucose. This hypoglycemic effect was explained by increased insulin levels and α-glucosidase inhibition (IC50:1.53 ± 0.03 μg/mL). This first study on the hypoglycemic activity of MC heartwood extract indicates that it could be a potential natural remedy for type 2 diabetes.

Salak seed extract (Salacca zalacca) is known for its high antioxidant content and low caffeine levels, making it a promising candidate for the development of value-added health products. However, there is a lack of scientific evidence for its anti-hyperglycemic effects. To address this, we investigated the in vitro and in vivo anti-hyperglycemic and antioxidant effects of salak seed extract. The HPLC chromatogram of salak seed extract shows a prominent peak that corresponds to chlorogenic acid. In vitro studies revealed that salak seeds inhibited α-glucosidase activity and glucose uptake in Caco-2 cells in a concentration-dependent manner, while also exhibiting antioxidant properties. The extract exhibits a non-competitive inhibition on α-glucosidase activity, with an IC₅₀ and K_i of 16.28 ± 7.22 and 24.81 μg/mL, respectively. In vivo studies utilizing streptozotocin-nicotinamide-induced diabetic mice showed that the extract significantly reduced fasting blood glucose (FBG) levels in the oral glucose tolerance test. Continuous administration of the salak seed extract resulted in lower FBG levels by 13.8% as compared with untreated diabetic mice, although this change was not statistically significant. The estimated LD₅₀ value of salak seed extract exceeds 2000 mg/kg, and no toxicity symptoms have been detected. Our research supports that salak seed extract has the potential to serve as a functional food or supplement that may be beneficial in reducing postprandial hyperglycemia among people with type 2 diabetes. This effect was explained by the salak’s inhibitory mechanisms of glucose absorption due to inhibition of both α-glucosidase activity and intestinal glucose uptake, coupled with its antioxidant effects.

Direct evidence of Triphala-drug interactions has not been provided to date. This study was aimed to determine the effects of Triphala on cytochrome P450 (CYP) isoforms and P-glycoprotein (P-gp) in vitro, and to investigate pharmacokinetic interactions of Triphala with CYP-probes in rats. Effects of Triphala on the activities of CYP isoforms and P-gp were examined using human liver microsomes (HLMs) and Caco-2 cells, respectively. Pharmacokinetic interactions between Triphala and CYP-probes (i.e., phenacetin and midazolam) were further examined in rats. Triphala extract inhibited the activities of CYP isoforms in the order of CYP1A2>3A4>2C9>2D6 with the IC₅₀ values of 23.6 ± 9.2, 28.1 ± 9.8, 30.41 ± 16.7 and 93.9 ± 27.5 μg/mL, respectively in HLMs. It exhibited a non-competitive inhibition of CYP1A2 and 2C9 with the K_i values of 23.6 and 30.4 μg/mL, respectively, while its inhibition on CYP3A4 was competitive manner with the Ki values of 64.9 μg/mL. The inhibitory effects of Triphala on CYP1A2 and 3A4 were not time-dependent. Moreover, Triphala did not affect the P-gp activity in Caco-2 cells. Triphala, after its oral co-administration at 500 mg/kg, increased the bioavailabilities of phenacetin and midazolam by about 61.2% and 40.7%, respectively, in rats. Increases observed in the bioavailabilities of phenacetin and midazolam after oral co-administration of Triphala in rats provided a direct line of evidence to show Triphala-drug interactions via inhibition of CYP1A and CYP3A activities, respectively. These results, together with the lack of time-dependency of CYP 1A2 and 3A4 inhibition in vitro, suggested that the inhibitory effect of Triphala is primarily reversible.

The objectives of the present study were to demonstrate the antihyperuricemic effect of triphala, a formulation of traditional Ayurvedic medicine, in potassium oxonate-induced hyperuricemic mice in vivo, and to examine its inhibitor effects on xanthine oxidase (XOD), inflammatory mediators and DPPH radicals in vitro. The water extract of triphala was determined to contain the total phenolics and total flavonoids of 317.6 ± 9.2 mg GAE/g and 7.73 ± 0.26 mg QE/g, respectively. Oral administrations of triphala significantly reduced the plasma uric acid levels of potassium oxonate-induced hyperuricemic mice at doses of 1,000 and 1,500 mg/kg, as compared with control ( p<0.05). Moreover, both doses of triphala treatments markedly inhibited the formation of uric acid due to inhibition of XOD activity in liver homogenates extracted from the hyperuricemic mice by about 70-80%. Lineweaver-Burk analysis of enzyme-kinetic data showed that triphala exhibited non-competitive inhibition on XOD activity in vitro with an inhibitory constant (Ki) of 590 μg/mL. Furthermore, triphala significantly suppressed the mRNA expressions of COX-II, TNF-α and iNOS in LPS-stimulated RAW 264.7 cells, as compared with control ( p <0.05), and decreased the expression of TGF-β. IC₅₀ values for inhibition of DPPH radical formation was calculated to be 21.9 ± 2.50 μg/mL. Antioxidant activities of triphala were determined to be 0.81 ± 0.07 g TEAC/g and 6.78 ± 0.29 mmol/100g, respectively, as assessed by ABTS and FRAP assays. In conclusion, this study provided in vivo and in vitro mechanistic evidence for the antihyperuricemic, antioxidative and anti-inflammatory effects of triphala for the first time, rationalizing its therapeutic usage for the treatment of hyperuricemia of gout.