Age-related changes in meningeal lymphatic function are closely associated with vascular endothelial growth factor-C expression.

Meningeal lymphatic vessels (MLVs) have crucial roles in removing metabolic waste and toxic proteins from the brain and transporting them to the periphery. Aged mice show impaired meningeal lymphatic function. Nevertheless, as the disease progresses, and significant pathological changes manifest in the brain, treating the condition becomes increasingly challenging. Therefore, investigating the alterations in the structure and function of MLVs in the early stages of aging is critical for preventing age-related central nervous system degenerative diseases. We detected the structure and function of MLVs in young, middle-aged, and aged mice. Middle-aged mice, compared with young and aged mice, showed enhanced meningeal lymphatic function along with MLV expansion and performed better in the Y maze test. Moreover, age-related changes in meningeal lymphatic function were closely associated with vascular endothelial growth factor-C (VEGF-C) expression in the brain cortex. Our data suggested that the cerebral cortex may serve as a target for VEGF-C supplementation to ameliorate meningeal lymphatic dysfunction, thus providing a new strategy for preventing age-related central nervous system diseases.

Personalised lamellar keratoplasty and keratopigmentation in Asian corneal leucoma patients.

OBJECTIVE: To describe a personalised lamellar keratoplasty (LK) associated with the keratopigmentation (KTP) technique for corneal leucoma among Asian patients. METHODS: This report was a non-randomised, retrospective clinical study performed in 32 consecutive eyes of 32 patients to improve cosmetic appearance. Twenty-two patients underwent LK combined with KTP, either by intralamellar or superficial route. Ten patients underwent the single personalised keratopigmentation method. The subjective and objective cosmetic results, ocular irritation, colour fading, neovascularisation formation and incidence of immune rejection were evaluated until three years after surgery. RESULTS: No complications occurred, and the corneal leucoma was successfully stained with India ink in all 32 patients. Most of the patients showed good cosmetic appearance. Pain, conjunctival congestion, corneal edema and foreign body sensation disappeared gradually within two to three weeks after surgery in all patients. Graft swelling, non-healing, or detaching was not observed during follow-up. However, two patients had slight opacity three years after LK. Colour fading was observed in one patient who underwent intralamellar corneal staining 10 months after surgery. Re-staining was performed. CONCLUSION: KTP combined with personalised LK is an effective personalised technique that presents long-standing colour staining and good cosmetic efficacy.

Bioactive lipids in pathological retinopathy.

Diabetic retinopathy is a common condition that occurs in patients with diabetes with long-standing hyperglycemia that is characterized by inappropriate angiogenesis. This pathological angiogenesis could be a sort of physiological proliferative response to injury by the endothelium. Recent studies suggested that reactive oxygen species (ROS) play a significant role in this angiogenesis. Vascular endothelial growth factor (VEGF) is a potent angiogenic growth factor that plays a significant role in diabetic retinopathy. The interaction between VEGF and ROS, and theirs in turn with pro- and anti-inflammatory cytokines and anti-inflammatory bioactive lipid molecules such as lipoxins, resolvins, protectins, and maresins is particularly relevant to understand the pathophysiology of diabetic retinopathy and develop future therapeutic interventions.

Effect of α-linolenic acid on streptozotocin-induced diabetic retinopathy indices in vivo.

BACKGROUND AND AIMS: Both oxidative stress and inflammation play a significant role in the pathobiology of diabetic retinopathy. Increased consumption of polyunsaturated fatty acids (PUFAs) may prevent or postpone the occurrence of diabetic retinopathy. Hence, the effect of α-linolenic acid (ALA), an essential fatty acid, on oxidative stress, inflammatory indices and production of vascular endothelial growth factor (VEGF) in streptozotocin-induced diabetic retinopathy indices in vivo was studied. METHODS: Serum and retina concentrations of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), interleukin-6 (IL-6), plasma and retina concentrations of lipid peroxides and antioxidant enzymes were estimated in streptozotocin (STZ)-induced diabetic animals. RESULTS: STZ-induced diabetic rats had significantly higher levels of VEGF in the serum and retina and IL-6 in the serum, whereas BDNF was lower in the serum, all of which reverted to near normal in ALA-treated diabetic animals. STZ treatment decreased serum glutathione peroxidase levels, which was restored to normal by both pre- and post-ALA treatment groups. CONCLUSIONS: STZ-induced changes in serum glutathione peroxidase, BDNF, VEGF and IL-6 that reverted to near control by ALA treatment, especially in ALA + STZ group, lending support to the concept that both oxidative stress and inflammation participate in DR and ALA treatment is of benefit in its prevention.