A Systematic Review on the Increasing Incidence of Inflammatory Bowel Disease in Southeast Asia: Looking Beyond the Urbanization Phenomenon.

The incidence of inflammatory bowel disease (IBD) has been increasing in Southeast Asia (SEA) in tandem with its economic growth and urbanization over the past 2 decades. Specific characteristics of IBD in SEA are similar to East Asia and the West, such as the declining ratio of ulcerative colitis to Crohn's disease. However, exceptionally low familial aggregation is seen. Smoking is also not a common risk factor in patients with Crohn's disease. The incidence of perianal disease is higher in SEA than in Australia and is comparable to the West. In a multiracial population, such as Singapore and Malaysia, Indians have the highest incidence and prevalence rates, which are likely to be due to important putative mutations. For instance, a higher frequency of the NOD2 predisposing mutation SNP5 and IBD risk allele IGR2198a and IGR2092a were found in Indians. Although differences in the genetic constitution play an important role in the epidemiology and prognosis of IBD in SEA, the emergence of this disease offers a unique opportunity to identify potential exposomes that contribute to its pathogenesis.

The Effects of Tocotrienol on Gut Microbiota: A Scoping Review.

Gut dysbiosis has been associated with many chronic diseases, such as obesity, inflammatory bowel disease, and cancer. Gut dysbiosis triggers these diseases through the activation of the immune system by the endotoxins produced by gut microbiota, which leads to systemic inflammation. In addition to pre-/pro-/postbiotics, many natural products can restore healthy gut microbiota composition. Tocotrienol, which is a subfamily of vitamin E, has been demonstrated to have such effects. This scoping review presents an overview of the effects of tocotrienol on gut microbiota according to the existing scientific literature. A literature search to identify relevant studies was conducted using PubMed, Scopus, and Web of Science. Only original research articles which aligned with the review's objective were examined. Six relevant studies investigating the effects of tocotrienol on gut microbiota were included. All of the studies used animal models to demonstrate that tocotrienol altered the gut microbiota composition, but none demonstrated the mechanism by which this occurred. The studies induced diseases known to be associated with gut dysbiosis in rats. Tocotrienol partially restored the gut microbiota compositions of the diseased rats so that they resembled those of the healthy rats. Tocotrienol also demonstrated strong anti-inflammatory effects in these animals. In conclusion, tocotrienol could exert anti-inflammatory effects by suppressing inflammation directly or partially by altering the gut microbiota composition, thus achieving its therapeutic effects.

The impact of diet and ethnicity on gut microbiota variation in irritable bowel syndrome: A multi-center study.

BACKGROUND AND AIM: The gut microbiota in irritable bowel syndrome (IBS) is known to vary with diet. We aim to (i) analyze the gut microbiota composition of IBS patients from a multi-ethnic population and (ii) explore the impact of a low FODMAP diet on gastrointestinal symptoms and gut microbiota composition among IBS patients. METHODS: A multi-center study of multi-ethnic Asian patients with IBS was conducted in two phases: (i) an initial cross-sectional gut microbiota composition study of IBS patients and healthy controls, followed by (ii) a single-arm 6-week dietary interventional study of the IBS patients alone, exploring clinical and gut microbiota changes. RESULTS: A total of 34 adult IBS patients (IBS sub-types of IBS-D 44.1%, IBS-C 32.4%, and IBS-M 23.5%) and 15 healthy controls were recruited. A greater abundance of Parabacteroides species with lower levels of bacterial fermenters and short-chain fatty acids producers were found among IBS patients compared with healthy controls. Age and ethnicity were found to be associated with gut microbiota composition. Following a low FODMAP dietary intervention, symptom and quality of life improvement were observed in 24 (70.6%) IBS patients. Symptom improvement was associated with adherence to the low FODMAP diet (46.7% poor adherence vs 92.9% good adherence, P = 0.014), and gut microbiota patterns, particularly with a greater abundance of Bifidobacterium longum, Anaerotignum propionicum, and Blautia species post-intervention. CONCLUSION: Gut microbiota variation in multi-ethnic IBS patients may be related to dietary intake and may be helpful to identify patients who are likely to respond to a low FODMAP diet.

Tocotrienol in the Management of Nonalcoholic Fatty Liver Disease: A Systematic Review.

The increasing burden of nonalcoholic fatty liver disease (NAFLD) requires innovative management strategies, but an effective pharmacological agent has yet to be found. Apart from weight loss and lifestyle adjustments, one isomer of the vitamin E family-alpha-tocopherol-is currently recommended for nondiabetic steatohepatitis patients. Another member of the vitamin E family, tocotrienol (T3), has anti-inflammatory and antioxidant properties that reach beyond those of alpha-tocopherol, making it a potential agent for use in NAFLD management. This systematic review aimed to provide an overview of the effects of T3 supplementation on NAFLD from both clinical and preclinical perspectives. A literature search was performed in October 2022 using PubMed, Scopus and Web of Science. Original research articles reporting NAFLD outcomes were included in this review. The search located 12 articles (8 animal studies and 4 human studies). The literature reports state that T3 isomers or natural mixtures (derived from palm or annatto) improved NAFLD outcomes (liver histology, ultrasound or liver profile). However, the improvement depended on the severity of NAFLD, study period and type of intervention (isomers/mixture of different compositions). Mechanistically, T3 improved lipid metabolism and prevented liver steatosis, and reduced mitochondrial and endoplasmic reticulum stress, inflammation and ultimately liver fibrosis. In summary, T3 could be a potential agent for use in managing NAFLD, pending more comprehensive preclinical and human studies.

Relationship Amongst Vitamin K Status, Vitamin K Antagonist Use and Osteoarthritis: A Review.

Vitamin K is essential for the carboxylation of the vitamin K-dependent proteins that are responsible for the suppression of matrix calcification. The use of vitamin K antagonists (VKAs) in patients with cardiovascular diseases could affect protein carboxylation and lead to the development of osteoarthritis (OA). This review aims to summarise the current evidence for the relationship between VKAs and OA. The literature search revealed that in observation studies, good vitamin K status, as reflected by the circulating level or protein carboxylation status of vitamin K, is associated positively with improved joint structural and functional indices and negatively associated with OA incidence. By contrast, in limited retrospective and prospective studies, the use of VKAs is associated positively with OA occurrence and knee/hip replacement. Pharmacological interactions between VKAs and various OA therapeutic agents exist and require careful monitoring and dosing. In conclusion, further epidemiological studies are warranted to verify the relationship between VKA use and OA to strengthen the evidence. Given that VKA use exerts potentially negative effects on joint health, intervention is required to protect the quality of life and mobility of patients.