Table 2.
The direct and indirect regulatory effects of estrogen on GI function.
| Research Object | Research Method | Major Research Conclusion | References |
|---|---|---|---|
| Cell Line Experiments | The transfected (HeLa) or endogenous (HepG2, DLD1) ER α or ER β cell lines: PCR, ELISA, Western Bolt. | E2 has different effects on cell growth/apoptosis based on the presence of ER isomers. The ER β subtype has the ability to activate specific signaling pathways from the plasma membrane, which may demonstrate the role of E2 in inducing cancer cell proliferation or apoptosis. |
Acconcia F (48) |
| Female Rats | Animal Model Construction: OVX female rats. | E2 acting via ER α in c-NTS neurons, including neurons stimulated by CCK, is sufficient to inhibit feeding. | Thammacharoen S (49) |
| Rats | Animal Experiments: Messenger RNA Expression of OT by Real-Time PCR (qRT-PCR) | OT antagonist administered to E2 benzoate (EB)-treated rats reversed the effect of EB on food intake. Estrogen effects to decrease food intake may involve the OT pathway. | Sloan DK (50) |
| Rates | Animal Experiments: Isolation of Stomach SMCs. EILSA, qRT-PCR. | Estrogen enhances the effect of acetylcholine (ACh) - induced single gastric SMC contraction. Estrogen increases NO and cGMP levels, with higher levels compared to late pregnancy. |
Al-Shboul OA (55) |
| Women | Clinical case-control study: A meta-genome-wide association study performed to compare the gut microbiota of pre and post-menopausal women. | The gut microbiota of pre and post-menopausal women is different, producing different metabolites. | Zhao H (57) |
| Mice | Animal Experiments: WT and ER α-deficient (Esrra−/−) mice | ERR α mediated its protective effects by acting within the radio-resistant compartment of the intestine. The absence of ERR α lead to a decrease in diversity of the microbial community. |
Tran A (63) |
| Mice | Animal Experiments: Macro-genomics and Biochemical Analysis | The gut microbiota is another factor in the patho-physiology of obesity. The obesity is associated with changes in the relative abundance of the two bacterial divisions, F and the B. | Turnbaugh PJ (65) |
| Patients | Clinical case-control study: Real-Time PCR (qRT-PCR) | F/B ratio and gene expression levels were elevated in T2D patients. Firmicutes positively correlated with studied gene expressions (IL-1β,-6,-8, TLR 2, 4, and5). |
Bahar-Tokman H (66) |
| Patients | Clinical case-control study: 16 S ribosomal RNA gene sequencing. | The differences in gut microbiota among IBD have changed after biotherapy. The increase in the ratio of F/B may be a potential predictive factor for disease activity and treatment. |
Tsai YC (67) |
| Male Wistar albino Rats | Animal Experiments: gonadectomized rats | E2 pretreatment inhibited gastric motility. Sex steroids have a modulatory role on the feedback control of gastric motility induced by NO colonic distension. |
Güal O (85) |
IL, Interleukin; TLR, Toll-Like Receptor; RNA, Ribonucleic Acid; c-NTS, caudal Nucleus Tactus Solitaries; CCK, Cholecystokinin; OVX, Ovariectomized; ERRa, Estrogen-related receptor alpha.