METHODS: 12 rats were divided into test and control groups. On day 1, the animals were anaesthetized, and silk ligatures were ligated around 6 maxillary posterior teeth in each animal from both groups. Surgical induction of osteoarthritis was performed on the left knees in the test group. No knee surgeries were performed in the control group. The ligatures were kept in place for 30 days, at which time the animals were euthanatized, and the maxillae and knee joints were harvested and processed for histological analysis. The alveolar bone loss was assessed using a zoom stereomicroscope.

MATERIALS AND METHODS: In the present study, our objective was to explore the potential of Citrus aurantifolia peel extract (CAPE) on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) induced colitis in mice. Twenty-eight male Balb/c mice were divided into four groups: (1) normal group, (2) TNBS group, (3) 125 mg/kg CAPE group and (4) 250 mg/kg CAPE group. Colitis was induced through rectal administration of TNBS. The anti-inflammatory effects of CAPE against colitis were assessed by body weight, DAI score, colonic length, weight-to-length ratio, haematology profile and histopathological examinations.

RESULTS: Our results showed that CAPE maintained the body weight of mice, repressed the increase of DAI score, maintained mice colonic length and weight, improved blood profile and suppressed the excessive production of TNF-α, IL-6 and IL-1β. Furthermore, CAPE improved the histopathological score of colitis mice.

OBJECTIVES: The aim of this study was to determine the efficacy of an injectable HA hydrogel to maintain disc height and tissue hydration, promote structural repair, and attenuate inflammation and innervation in the lumbar discs.

SUMMARY OF BACKGROUND DATA: Previously, we have demonstrated that HA hydrogel alleviated inflammation, innervation, and pain to promote disc repair. Nevertheless, the effect of an injectable HA hydrogel in the lumbar disc in a weight-bearing animal model was not performed.

METHODS: We have adopted a surgically puncture-induced disc injury at lumbar levels in a rabbit model. The discs were grouped into sham, puncture with water injection, and puncture with HA hydrogel injection. Postoperatively, we measured changes in disc height using x-ray. We used magnetic resonance imaging to assess disc degeneration on tissue hydration after euthanasia. Post-mortem, we determined histological changes, innervation (PGP9.5) and inflammation (interleukin [IL]-6, IL-1β, and tumor necrosis factor [TNF]-α) in the discs.

RESULTS: We have demonstrated a significant reduction of disc height and T2/T1ρ mapping with histological evidence of degenerative discs, increase of innervation and inflammation in puncture-induced disc injury over time. In the HA hydrogel group, disc height was increased at weeks four and eight. A slight increase of T2 mapping, but significantly in T1ρ mapping, was observed in the HA hydrogel group at week 8. We observed homogenous NP distribution and organised AF lamellae at week eight and a slight reduced innervation score in the treatment group. HA hydrogel significantly downregulated IL-6 expression at day 1. This, however, was only slightly reduced for IL-1β and TNF-α.