{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:14:58Z","timestamp":1760242498949,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,7,26]],"date-time":"2017-07-26T00:00:00Z","timestamp":1501027200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Type 2 diabetes remains one of the leading causes of death worldwide. Persistent hyperglycemia within a diabetic state is implicated in the generation of oxidative stress and aggravated inflammation that is responsible for accelerated modification of pancreatic beta cell structure. Here we investigated whether a lanosteryl triterpene, methyl-3\u03b2-hydroxylanosta-9,24-dien-21-oate (RA-3), isolated from Protorhus longifolia can improve glucose tolerance and pancreatic beta cell ultrastructure by reducing oxidative stress and inflammation in high fat diet and streptozotocin-induced type 2 diabetes in rats. In addition to impaired glucose tolerance, the untreated diabetic rats showed increased fasting plasma glucose and C-peptide levels. These untreated diabetic rats further demonstrated raised cholesterol, interleukin-6 (IL-6), and lipid peroxidation levels as well as a destroyed beta cell ultrastructure. Treatment with RA-3 was as effective as metformin in improving glucose tolerance and antioxidant effect in the diabetic rats. Interestingly, RA-3 displayed a slightly more enhanced effect than metformin in reducing elevated IL-6 levels and in improving beta cell ultrastructure. Although the involved molecular mechanisms remain to be established, RA-3 demonstrates a strong potential to improve pancreatic beta cell ultrastructure by attenuating impaired glucose tolerance, reducing oxidative stress and inflammation.<\/jats:p>","DOI":"10.3390\/molecules22081252","type":"journal-article","created":{"date-parts":[[2017,7,26]],"date-time":"2017-07-26T11:45:01Z","timestamp":1501069501000},"page":"1252","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["A Lanosteryl Triterpene from Protorhus longifolia Improves Glucose Tolerance and Pancreatic Beta Cell Ultrastructure in Type 2 Diabetic Rats"],"prefix":"10.3390","volume":"22","author":[{"given":"Sihle","family":"Mabhida","sequence":"first","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rebamang","family":"Mosa","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dambudzo","family":"Penduka","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Foluso","family":"Osunsanmi","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5965-3610","authenticated-orcid":false,"given":"Phiwayinkosi","family":"Dludla","sequence":"additional","affiliation":[{"name":"Biomedical Research and innovation Platform (BRIP), South African Medical Research Council, Tygerberg 7505, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tryana","family":"Djarova","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andy","family":"Opoku","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,7,26]]},"reference":[{"key":"ref_1","unstructured":"International Diabetes Federation (IDF) (2017, May 29). 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