METHODS: Presently, we provide a review of key studies evaluating the effects of dietary flavonoids in different stages of adipocyte development with a particular emphasis on the investigations that explore the underlying mechanisms of action of these compounds in human or animal cell lines as well as animal models.
RESULTS: Flavonoids have been shown to regulate several pathways and affect a number of molecular targets during specific stages of adipocyte development. Although most of the studies reveal anti-adipogenic effect of flavonoids, some flavonoids demonstrated proadipogenic effect in mesenchymal stem cells or preadipocytes.
CONCLUSION: The anti-adipogenic effect of flavonoids is mainly via their effect on regulation of several pathways such as induction of apoptosis, suppression of key adipogenic transcription factors, activation of AMPK and Wnt pathways, inhibition of clonal expansion, and cell-cycle arrest.
METHODS: Electronic databases including CENTRAL, CINAHL, EMBASE, MEDLINE were searched up to April 2018 for relevant RCTs. Journal and conference proceedings were also searched. Two review authors independently selected trials, extracted data, assessed the risks of bias in included trials and graded the quality of evidence. Meta-analyses were conducted for studies presenting similar outcomes.
RESULTS: Ten RCTs involving 1164 participants were included. These RCTs varied in terms of patients' grade of haemorrhoids, length of trials, and outcome assessed. Most of the studies did not describe adequately the process of randomisation and allocation concealment. The pooled analysis of data from three studies indicated that there was significant difference between groups for the bleeding outcome, favoring the MPFF group (RR 1.46; 95% CI 1.10-1.93; p = 0.008). Except for bleeding, the current evidence did not show MPFF has significant effects on all the other outcomes examined when compared with placebo. Even then, the quality of evidence for bleeding was judged as low due to the small number and inconsistent results among the included studies.
CONCLUSION: This review highlights the need for further rigorous research if MPFF was to be routinely used for the treatment of haemorrhoid symptoms.