Fig 1.
Complete Freund’s adjuvant (CFA) or vehicle was intraarticularly injected at Day 0. Pain withdrawal threshold and swelling assessments were examined at timepoints of Pre-CFA, Pre-treatment and Post-treatment. Three days after injection of CFA (Day 3), animals were treated with laser acupuncture (LA) and sham-operated LA (sLA). Following the 10-day treatment (Day 13), animals were sacrificed for histology and immunohistochemistry assays.
Fig 2.
Development of ankle circumference (A) and pain withdrawal threshold (B) in vehicle injection, CFA-induced arthritic rats treated with laser acupuncture (LA) and sham-operated laser acupuncture (sLA) at timepoints of before CFA injection (Pre-CFA), before and after treatments (Pre-treatment and Post-treatment). Values are means ± SD. * indicates a significant change in the parameter assessed (P < 0.05), when values are compared with vehicle control values. # indicates a significant change in the parameter assessed (P < 0.05), when values are compared with sLA values.
Fig 3.
Representative HE sections of the hind paws obtained from vehicle (A) and CFA-induced arthritic animals treated with sham-operated and laser acupuncture (sLA and LA, B and C). Histology showed articular cartilage changes (A-C) and synovial (syn) inflammation (a-c) in the CFA-injected side of sLA and LA groups when compared to the vehicle side. The articular cartilage surface was smooth and evenly stained on the vehicle control side of each group, but there were apparent articular cartilage fissures, extending from the surface to the depth with significant loss of staining in the sLA group. Synovium showed thickening and widening of the synovial membrane and infiltration of inflammatory cells being less in rats from the LA groups (c) and apparent in rats of sLA group (b). The bar graph shows a statistical difference in the area of infiltrating inflammatory cells among the ankles treated with vehicle, sLA, and LA (D). Each value represents the mean ± SD. Values in each bar with different italic letters (a,b,c) indicate significant difference at confidence level of P < 0.05 tested by the Scheffé post hoc test. The arrows indicate areas of cartilage disruption and chondrocyte disorientation with clusters of chondrocytes. The arrowheads indicate areas of inflammatory cell infiltration in synovium.
Fig 4.
Representative images of surface cartilage damage at the tibial plateau with collagen type II (CoII) immunoreactivity and safranin O/Fast Green staining in vehicle control (A and a), CFA combined with sham-operation (sLA, Band b) and laser acupuncture (LA, C and c) (sLA and LA) groups, respectively. At higher-power magnification, it is evident that marked increase of positive collagen type II immunoreactivities (brown staining) and proteoglycan safranin O (dark orange) were clearly localized in the LA group compared with sLA. Quantitative analysis of positive-labeled cells in cartilage for safranin O (D) and collagen type II immunohistochemistry (d) in each group was presented in mean ± SD. Different italic letters (a,b,c) indicate significant differences between groups using Scheffe’s post hoc test (P < 0.05). A scale bar indicates 50 μm.
Fig 5.
The immunofluorescent expressions of COMP (Alexa Fluor 488-green) and TNF-α (Alexa Fluor 594-red) immunoreactivity in the vehicle control (A and a), CFA combined with sham-operation (sLA, B and b) and laser acupuncture (LA, C and c) groups, respectively. The level of COMP- and TNF-α-like immunoreactivity were counted in five randomly selected high-power fields (×200) in each section (D and d). The bar graph shows a statistical difference in the COMP- and TNF-α-like immunoreactive cells among the vehicle control, sLA and LA groups. A decrease in COMP expression and elevation in TNF-α expression in the cartilage from the sLA group were noted compared with the vehicle control and LA groups. Each value represents the mean ± SD. Different italic letters indicate significant differences between groups using Scheffe’s post hoc test (P < 0.05). A scale bar indicates 50 μm.