ABSTRACT
<p><b>OBJECTIVE</b>To observe the effects of close-to-bone needling (CBN) on the expressions of type-Ⅱcollagen, pro-collagen type Ⅱ C-terminal propeptide (PⅡCP) and C-telopeptide of type Ⅱ collagen (CTX-Ⅱ) in rabbits with knee osteoarthritis (KOA).</p><p><b>METHODS</b>Among 40 New Zealand rabbits, 10 rabbits were selected into a normal group; the remaining 30 rabbits were made into KOA model, and X-ray was used to evaluate the results of model establishment. After the model was successfully made, the rabbits were randomly divided into a model group, a CBN group and a regular acupuncture group, ten rabbits in each one.Rabbits in the CBN group and the regular acupuncture group were treated at "Neixiyan" (EX-LE 4), "Dubi" (ST 35), "Yinlingquan" (SP 9), "Zusanli" (ST 36) and "Liangqiu" (ST 34). The CBN group applied CBN, and the depth of needling was appropriate with needles reaching bone; the regular acupuncture group applied regular acupuncture. The electroacupuncture(EA) device was used in the two groups, 20 min per treatment, once a day.Five days of treatment were taken as one course, and totally 4 courses were given with an interval of 2 days between courses. The normal group received identical fixation as model group. After treatment, magnetic resonance imaging (MRI) was used to perform imaging observation on knee; transmission electron microscopy (TEM) was used to observe the cell structure of knee joint cartilage;HE staining was used to observe the pathological change of knee; TUNEL was used to observe the apoptotic index; the expressions of type-Ⅱ collagen proteins and mRNA were measured by Western-blot and reverse transcription-polymerase chain reaction (RT-PCR); the serum PⅡCP and CTX-Ⅱ levels were measured using enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>After treatment, compared with the model group, in the CBN group and regular acupuncture group the articular cavity effusion was reduced without the subchondral bone edema; the cell structure of knee joint cartilage was regular with less apoptosis; the expressions of type-Ⅱ collagen proteins and mRNA were significantly increased (all<0.05), the PⅡCP levels were significantly increased (both<0.05), but the CTX-Ⅱ levels were significantly decreased (both<0.05).The differences of the expressions of type-Ⅱ collagen proteins and mRNA, the levels of PⅡCP and CTX-Ⅱ between the CBN group and the regular acupuncture group were significant (all<0.05); the differences between the CBN group and the normal group were non-significant (all>0.05).</p><p><b>CONCLUSIONS</b>CBN can significantly improve the pathological status of cartilage of KOA, reduce apoptosis, and is likely to regulate the expressions of PⅡCP and CTX-Ⅱ to promote the type-Ⅱ collagen, which is superior to regular acupuncture.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To observe the effects of close-to-bone needing combined with electroacupuncture (EA) on cartilage collagen type Ⅱ/discoidin domain receptor/matrix metalloproteinase 13 (collagen type Ⅱ/DDR2/MMP 13) signaling pathway in rabbits with knee osteoarthritis (KOA), and to explore the possible action mechanism of this method on repair of extracellular matrix of knee cartilage.</p><p><b>METHODS</b>Forty New Zealand white rabbits were randomly assigned into a normal group (10 rabbits) and a model establishing group (30 rabbits). The Hulth-Telhag technique was applied to establish the model of KOA, and X-ray was used for outcome assessment. The rabbits with successful modeling were randomly assigned into a model group, a close-to-bone needing group, a regular acupuncture group, 10 rabbits in each one. The rabbits in the close-to-bone needing group were treated with close-to-bone needing and EA; the rabbits in the regular acupuncture group were treated with regular acupuncture and EA. "Neixiyan" (EX-LE 4), "Dubi" (ST 35), "Yinlingquan" (SP 9), "Zusanli" (ST 36) and "Liangqiu" (ST 34) were selected in the two groups. The intervention was given for 20 min, once a day; the intervention of 5 days made 1 session, 2 days as the interval and totally 4 sessions were given. Rabbits in normal and model group were immobilized without any treatment. After the treatment, western blotting method was applied to evaluate the expression of DDR2 and collagen type Ⅱ; the activity of collagen type Ⅱ, DDR2 and MMP 13 was assessed by immunohistochemistry method; the mRNA expression of DDR2 and MMP 13 was determined by reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Compared with the normal group, the activity expression of collagen type Ⅱ were significantly reduced in the other groups (all<0.01),while the activity and mRNA expression of DDR2 and MMP 13 were notably increased (all<0.01). Compared with the model group, the activity expression of collagen type Ⅱ in the close-to-bone needing group and regular acupuncture group were increased (all<0.01), while the activity and mRNA expression of DDR2 and MMP 13 were reduced (all<0.01). Compared with the regular acupuncture group, the activity and mRNA expression of MMP 13 and DDR2 in the close-to-bone needing group were reduced (all<0.01), while the activity expression of collagen type Ⅱ were increased (<0.01).</p><p><b>CONCLUSIONS</b>The close-to-bone needing combined with EA and regular EA could both promote the repair of knee cartilage, where closing-to-bone needing combined with EA shows a superior efficacy. The mechanism may be associated with the blocking effect of collagen type Ⅱ/DDR2/MMP13 signaling pathway and the inhibiting effect of degradation in extracellular matrix of cartilage.</p>