Methods: Sprague-Dawley female rats were ovariectomized or sham-operated and divided into four groups: sham-operated rats fed a normal diet (ND); ovariectomized rats fed a normal diet (OVX-ND); sham-operated rats fed a HFSD; ovariectomized rats fed a high-fat style diet (OVX-HFSD). Mean blood pressure and fasting blood glucose were measured on weeks 0 and 10. The rats were sacrificed 10 weeks after initiation of ND or HFSD, the kidney and liver were harvested for histological, immunohistochemical and immunofluorescence studies.
Results: HFSD-fed rats presented a significantly greater adiposity index compared to their ND counterparts. Liver index, fasting blood glucose and mean blood pressure was increased in OVX-HFSD rats compared to HFSD rats at study terminal. Histological and morphometric studies showed focal interstitial mononuclear cell infiltration in the kidney of HFSD rats with mesangial expansion being greater in the OVX-HFSD rats. Both HFSD fed groups showed increased expressions of renal inflammatory markers, namely TNF-alpha, IL-6 and MCP-1, and infiltrating M1 macrophages with some influence of ovarian hormonal status. HFSD-feeding also caused hepatocellular steatosis which was aggravated in ovariectomized rats fed the same diet. Furthermore, hepatocellular ballooning was observed only in the OVX-HFSD rats. Similarly, HFSD-fed rats showed increased expressions of the inflammatory markers and M1 macrophage infiltration in the liver; however, only IL-6 expression was magnified in the OVX-HFSD.
Conclusion: Our data suggest that some of the structural changes and inflammatory response in the kidney and liver of rats fed a HFSD are exacerbated by ovariectomy.
CLINICAL CASE: A 56-year-old Chinese woman, an active smoker, presented with a hearing deficit, persistent tinnitus and nasal congestion. Examination and investigations revealed the presence of a mass in the nasopharynx. Tissue biopsy revealed nasopharyngeal carcinoma. However, the Epstein-Barr virus was not tested. She was counseled for chemotherapy, but refused and was subsequently lost to follow up. She presented one year later with right eye ptosis associated with progressive worsening of diplopia and blurring of vision. Examination revealed multiple (second, third, fourth and sixth) cranial nerve involvement. Systemic examination and investigations revealed cervical lymphadenopathy and liver metastasis. Repeated imaging showed that the mass had invaded the base of the skull, cavernous sinus and orbital apices. Pulse dosing of corticosteroid therapy was commenced, resulting in dramatic improvement of vision.
CONCLUSION: Optic neuropathy may be the presenting sign of NPC. Corticosteroid therapy can offer immediate visual improvement.