[Effects of catgut embedding and PGLA embedding at "Zusanli" (ST 36) on skin mast cells, substance P and histamine in healthy rats].

OBJECTIVE: To observe the effects of catgut embedding and polyglycolic acid/poly-lactic acid (PGLA) embedding at "Zusanli" (ST 36) on the activation of local skin mast cells (MC), and expression of substance P (SP) and histamine (HA), and to explore the mechanism of the temporal stimulation effect of acupoint catgut embedding and provide a foundation for further research on the initiation mechanism of acupoint catgut embedding. METHODS: One hundred and sixty male SPF-grade SD rats were randomly divided into a blank group (10 rats), a sham-embedding group (50 rats), a catgut group (50 rats), and a PGLA group (50 rats). Each intervention group was further randomly divided into five subgroups according to the time points after intervention: 8 hours, 3 days, 7 days, 14 days, and 21 days, with 10 rats in each subgroup. One-time sham-embedding, catgut embedding and PGLA embedding was given at left "Zusanli" (ST 36) in each intervention group, respectively. The skin and subcutaneous connective tissue of the left "Zusanli" (ST 36) were collected at the corresponding time points after intervention, except for the blank group (only one day before intervention). Toluidine blue staining was used to detect MC count and degranulation, and immunohistochemical staining was used to detect the expression of SP and HA positive cells. RESULTS: There was no significant difference in MC count between the subgroups of each intervention group and the blank group (P>0.05). There was no significant difference in MC count between the subgroups of the catgut group and the PGLA group (P>0.05). The MC count in the 8-hour subgroup of PGLA group was higher than that in the 8-hour subgroup of catgut group (P<0.05), while the MC count in the 21-day subgroup of PGLA group was lower than that in the 21-day subgroup of catgut group (P<0.05). Compared with the blank group, the degranulation rates of MC were increased in the 8-hour and 3-day subgroups of sham-embedding group, 8-hour, 3-day, and 7-day subgroups of catgut group, and 8-hour, 3-day, 7-day, and 14-day subgroups of PGLA group (P<0.01, P<0.05, P<0.001). There was no significant difference in the degranulation rate of MC between the subgroups of the catgut group and the PGLA group (P>0.05), and no significant difference in the degranulation rate of MC between the two embedding groups at the same time point (P>0.05). Compared with the blank group, the expression of SP positive cells was increased in the 8-hour subgroup of sham-embedding group, 8-hour, 3-day, 7-day, and 14-day subgroups of catgut group, and 3-day, 7-day, and 14-day subgroups of PGLA group (P<0.001, P<0.05). The expression of SP positive cells in the 7-day subgroup of catgut group was higher than that in the 8-hour subgroup of catgut group (P<0.05), while the expression of SP positive cells in the 14-day subgroup of catgut group was lower than that in the 7-day subgroup of catgut group (P<0.001). The expression of SP positive cells in the 7-day subgroup of PGLA group was higher than that in the 3-day subgroup of PGLA group (P<0.05), while the expression of SP positive cells in the 14-day subgroup of PGLA group was lower than that in the 7-day subgroup of PGLA group (P<0.01). There was no significant difference in the expression of SP positive cells between the subgroups of the two embedding groups at the same time point (P>0.05). Compared with the blank group, the expression of HA positive cells was increased in the 8-hour, 3-day subgroups of sham-embedding group, 8-hour, 3-day, 7-day, and 14-day subgroups of catgut group, and 8-hour, 3-day, 7-day, 14-day, and 21-day subgroups of PGLA group (P<0.001, P<0.01, P<0.05). The expression of HA positive cells in the 14-day subgroup of catgut group was lower than that in the 7-day subgroup of catgut group (P<0.05), while the expression of HA positive cells in the 3-day subgroup of PGLA group was higher than that in the 8-hour subgroup of PGLA group (P<0.05), and the expression of HA positive cells in the 14-day subgroup of PGLA group was lower than that in the 7-day subgroup of PGLA group (P<0.05). The expression of HA positive cells in the 3-day subgroup of PGLA group was higher than that in the 3-day subgroup of catgut group (P<0.05). CONCLUSION: Catgut and PGLA embedding at "Zusanli" (ST 36) in healthy rats could induce changes in local skin MC, SP, and HA, which may be one of the mechanisms of the temporal stimulation effect after acupoint embedding. There are certain differences between different suture materials. A moderate inflammatory response in the acupoint area, mediated by MC and involving SP and HA, may be one of the initiating factors for the effect of acupoint catgut embedding.

[Effect of catgut implantation on macrophage CD68, tumor necrosis factor-α and interleukin-1ß in "Zusanli" (ST 36) region of rats].

OBJECTIVE: To observe the expression of local macrophages and related cytokines tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) after catgut implantation in "Zusanli"(ST 36) in rats, so as to explore its underlying mechanisms in inducing therapeutic effect. METHODS: A total of 110 male SD rats were randomly divided into blank control group (n=10), catgut embedding (CE) group (n=50), and sham CE group (n=50). The CE and sham CE groups were randomly divided into 8 h, 3 d, 7 d, 14 d and 21 d subgroups after the intervention (n=10 in each time point group). Rats of the CE group were uniformly subjected into catgut embedding at ST36 once, and those of the sham CE group received embedding needle puncture at ST36 without catgut retention, and the blank control group was only grasped and fixed without other treatments. Tissues from the ST36 area in each group were collected at the corresponding time points, and the expression of CD68 in macrophages in the acupoint area was detected by immunofluorescence, the contents of TNF-α and IL-1ß in the acupoint area were detected by ELISA. RESULTS: Following catgut embedment at ST36, the contents of TNF-α and IL-1ß, and macrophage CD68 expression level began to increase at 8 h, peaked at 3 d, and then gradually decreased at 7, 14, and 21 d, being still higher in the CE group than in the blank control group at 21 d (P<0.05). Compared with the blank control group, the contents of TNF-α and IL-1ß, and macrophage CD68 expression were significantly increased at 8 h, and 3, 7, 14 and 21 d in the CE group (P<0.05). Following sham CE at ST36, the content of TNF-α at 8 h and 3 d, IL-1ß at 8 h and 3, 7 and 14 d, and expression of CD68 at 8 h were significantly increased in comparison with the blank control group (P<0.05). Comparison between the CE and sham CE groups showed that the contents of IL-1ß at 3, 7, 14 and 21 d, and contents of TNF-α，CD68 expression at 8 h, and 3, 7, 14 and 21 d were significantly higher in the CE group than in the sham CE group (P<0.05). CONCLUSION: Catgut embedding at ST36 can induce an increase levels of inflammatory cytokines TNF-α, IL-1ß and macrophage CD68 in the local microenvironment in rats, which may contribute to its functions in initiating therapeutic effect.

[Bibliometric analysis on key elements of clinical application of acupoint catgut embedding therapy in recent ten years].

OBJECTIVE: To analyze the characteristics of acupoint catgut embedding methods, tools, catgut types, and the treatment cycles in the clinical research in recent ten years both at home and abroad, so as to summarize its regularities and to provide technical references for further studies. METHODS: Articles about clinical researches on catgut embedding therapy published in recent ten years (from January 1, 2010 to December 31,2020) were retrieved from the databases of CNKI, Wanfang, VIP, and PubMed by using key words of "acupoint embedding" "acupoint catgut embedding" and "catgut implantation at acupoint". According to the inclusion and exclusion criteria, a new database was established for analyzing the data mentioned above. RESULTS: 1) A total of 1 196 articles were collected, including 15 English articles and 1 181 Chinese articles, presenting a fluctuating increasing trend in recent ten years. 2) The commonly used acupoint embedding methods included disposable catgut embedment needle method (399 times, 38.89%) and disposable syringe needle catgut embedding method (347 times, 33.82%), for which two or multiple methods were mentioned in the same one article. 3) The most frequently used top two tools for catgut embedding were the dispo-sable catgut embedment needle (463 times, 43.03%) and disposable syringe needle (406 times,37.73%), with a significant increase in the application of disposable syringe needle. The most commonly used size of tools included No. 7 (283 times, 39.86%), No. 9 (196 times, 27.61%) and No. 8 (109 times, 15.35%). 4) The most frequently implanted surgical suture was still the common catgut (671 times, 58.15%) despite of a reduction in clinical application year by year, and the types of the implanted suture materials were gradually enriched since 2018, such as the absorbable surgical suture, polyethylprolactide(PGLA), collagen protein thread, polydioxanone(PPDO), etc. The commonly used implanted catgut size was 3-0 (227 times, 30.15%), 2-0 (176 times, 23.37%), 4-0 (131 times, 17.40%), 0 (103 times, 13.68%), with the commonly used catgut length being 1 cm (332 times, 35.55%), 1.5 cm (103 times, 11.03%), 1-2 cm (92 times, 9.85%) and 2 cm (92 times, 9.85%). 5) The intervals of the catgut implantation were 7 days (313 times, 28.95%), 14 days (262 times, 24.24%), 10 days (174 times, 16.10%), and 15 days (162 times, 14.99%). CONCLUSION: In recent ten years, clinical research on acupoint catgut embedding is growing rapidly, and the embedding methods, tools, implanted sutures, and embedding intervals are various, which may provide certain technical references for the future researches and suggest an urgent need of formulation of the standardized and unified standards in this field.

[Time-effect reaction observation of micro-invasion embedded poly glycolide-co-lactide suture in Sanyinjiao (SP6) in healthy subjects by using magnetic resonance].

OBJECTIVE: To observe the time-effect of stimulation of the embedded poly glycolide-co-lactide (PGLA) suture in Sanyinjiao (SP6) area in normal human body, so as to provide an experimental evidence for clinical application of micro-invasion suture-embedding at an appropriate interval. METHODS: A total of 8 healthy volunteer students (3 boys and 5 girls, ranging in age from 24 to 27 years) were recruited in the present study. A piece of sterilized PGLA suture was implanted into the left SP6 using minimally invasive surgery after strict local skin disinfection. The fat-suppression T2 weighted magnetic resonance images (MRI, displaying local lesion after eliminating interference of fat tissue signals), and T2 mapping 8-echo train images were acquired before and 8 h, 3, 7, 10 and 14 days after PGLA suture embedment by using a MR imaging system. After transformation of the T2-mapping 8-echo train images into T2-mapping images by using a relevant software, the T2 values (meaning the relaxation time of the local muscle) of the left SP6 were measured, followed by analysis of the signal intensity of T2 weighted fat-suppression images and T2 values at different time-points. RESULTS: Before the suture embedding, no abnormal signals were found in the signal intensity of T2 weighted fat-suppression images. After PGLA suture embedment, the local signal intensity of T2WI fat-suppression images was relatively increased at the 8th h, and on day 3, 7, 10 and 14 relevant to pre-embedment, but gradually atte-nuated on day 10 and 14. The T2 values were significantly increased at the 5 time-points of post-embedment (all P<0.01), but without significant differences among the 8thh, the 3rd and 7thd (P>0.05), and being markedly lowered on day 14 relevant to day 7 (P<0.01) in spite of being still markedly higher than that of pre-embedding (P<0.01). CONCLUSION: The signal intensity of T2 weighted fat-suppression images and T2 values acquired from PGLA-suture-embedded SP6 acupoint area in healthy subjects may keep at least for 2 weeks, suggesting that the stimulating reaction of suture-embedment persists more than 14 days. Hence, when a micro-invasion embedding with PGLA suture performed, the interval of two weeks would be appropriate.

[Observation on time-effect for the stimulating at Zusanli (ST 36) with minimally invasive embedding with PGLA in the healthy person].

OBJECTIVE: To explore the objectivity and time-effect of stimulating effect at acupoint with PGLA in the healthy person, and to provide a basis for the rational interval of minimally invasive embedding of PGLA. METHODS: Before embedding, 8 h, 3rd, 7th, 10th, 14th day after embedding, medical imaging magnetic resonance imaging (MRI) scanning technique was used to collect local T2WI pressure-lowering and T2-Mapping 8 echoes sequence image of left Zusanli (ST 36) in 8 cases of healthy person. The T2-Mapping 8 echoes sequence image was generated by the relevant software to the T2-Mapping image and the local T2 value was measured. The characteristics of local T2WI pressure-fat image signal intensity and the change of T2 value at left Zusanli (ST 36) with minimally invasive embedding with PGLA were observed and analyzed. RESULTS: ①There was no abnormal signal on the T2WI pressure-fat image on the left Zusanli (ST 36) point before the embedding. The high-signal was seen on the local T2WI pressure-fat image at each time point after embedding, there was no significant difference in local signal intensity between 8 h, 3rd and 7th day after embedding. The local signal intensity decreased on the 10th day after embedding, and the local signal intensity decreased significantly on the 14th day after embedding.②The T2 value at each time point after embedding increased significantly compared with that before embedding (all P<0.01); there was no significant difference in T2 value among the 8 h, 3rd and 7th day after embedding (all P>0.05); there was no significant difference between the T2 value on the 7th and the 10th day after embedding (P>0.05)，the T2 value on the 14th day after embedding was significantly lower than that on the 7th day after embedding (P<0.01). CONCLUSION: It has a stimulating effect on the local acupoints with minimally invasive embedding with PGLA in the healthy person, and the stimulating effect has certain time-effect. The effective stimulation time is about 2 weeks. The rational interval period for the minimally invasive embedding with the PGLA of the same specification type should be about 2 weeks.

[Dynamic Changes of Fast Spin-echo T 2 Weighted Images Displayed Topical Reactions to Micro-invasive Catgut-embedment of Zusanli (ST 36) in Healthy Volunteer Subjects].

OBJECTIVE: To observe the duration of local reactions after subcutaneous micro-invasive catgut-embedding stimulation in Zusanli(ST 36) region in normal human body by using magnetic resonance (MR) T 2-mapping, so as to find a reasonable interval between every two catgut-embedding performance. METHODS: A total of 8 normal volunteers (3 women, and 5 men) were enrolled in the present study. Before and 8 h, and 3, 7, 14, 21, 28 and 35 days after the subcutaneous micro-invasive embedment of catgut (Gauge 2.0, 2 cm long) in the left Zusanli (ST 36) area, the local T 2-weighted images (T 2 WI) and fat-suppression T 2-weighted images (FS T 2 WI) were detected and recorded by using MR scan (GE Optima MR 360 1.5 T) and analyzed using FuncTool software. RESULTS: Compared with pre-catgut-embedment, the local signal strength of T 2 FS WI and T 2 relaxation time began to rise on the 8th hour after catgut-embedment, peaked on the 3rd day, began to descend on the 7th day, but being still higher than pre-embedment, and turned to the normal level on the 21st day to the 35th day. Results of statistical analysis displayed that compared with pre-catgut-embedment, T 2 relaxation time levels were significantly higher on the 8th h, day 3, 7 and 14 after the embedment (P<0.01), and were comparable to that of pre-embedment on day 21, 28 and 35 (P>0.05). CONCLUSIONS: Catgut-embedment of Zusanli (ST 36) induces an apparent change of MRI signals from the 8th h to the 14th day in normal volunteer subjects, suggesting that an interval of 21 days may be reasonable for the micro-invasion catgut-embedment in clinical practice.