Rotational thromboelastometry during Cesarean section as a predictive evaluation for the progression of persistent postpartum hemorrhage in parturients with placenta previa: A prospective observational study.

Background: The rotational thromboelastogram (ROTEM) has been used in the management of massive bleeding and transfusion strategy. This study investigated ROTEM parameters measured during Cesarean section as predictors for the progression of persistent postpartum hemorrhage (PPH) in parturients with placenta previa. Methods: This prospective observational study recruited 100 women scheduled for elective Cesarean section after being diagnosed with placenta previa. Recruited women were divided into two groups according to the amount of estimated blood loss: the PPH group (PPH > 1500 ml) vs. the non-PPH group. ROTEM with laboratory tests was performed three times, preoperative, intraoperative, and postoperative time, which were compared between the two groups. Results: The PPH and non-PPH groups included 57 and 41 women, respectively. The area under the receiver-operating characteristic curve of postoperative FIBTEM A5 to detect PPH was 0.76 (95% CI = 0.64 to 0.87; P < 0.001). When postoperative FIBTEM A5 was 9.5, the sensitivity and specificity were 0.74 (95% CI = 0.55 to 0.88) and 0.73 (95% CI = 0.57 to 0.86), respectively. When subgrouping the PPH group based on the postoperative FIBTEM A5 value of 9.5, intraoperative cEBL was similar between the two subgroups; however, postoperative RBC was transfused more in the subgroup with FIBTEM A5 < 9.5 than the subgroup with FIBTEM A5 ≥ 9.5 (7.4 ± 3.0 vs 5.1 ± 2.3 units, respectively; P = 0.003). Conclusion: Postoperative FIBTEM A5, with appropriate selection of the cut-off value, can be a biomarker for more prolonged PPH and massive transfusion following Cesarean section by placenta previa.

The influence of preoperative epidural labor analgesia on postoperative pain in parturients undergoing emergency cesarean section : A retrospective analysis.

BACKGROUND: Intense noxious input from the periphery may result in central sensitization and hyperexcitability, thus accentuating subsequent postoperative pain. Parturients who undergo emergency cesarean section (C-sec) after experiencing labor pain often develop labor pain-induced sensitization. OBJECTIVE: This retrospective study evaluated whether parturients without epidural labor analgesia (ELA) who underwent emergency C­sec, experienced more severe postoperative pain and required more rescue analgesics during the postoperative period. METHODS: The institution's medical database was searched for parturients who underwent emergency C­sec under spinal anesthesia for any reason between January 2013 and December 2016. Those who underwent elective C­sec under spinal anesthesia were included as the reference arm. Parturients were divided into three groups: ELA, no-ELA and elective. Characteristics of patients and perioperative outcomes were evaluated. As primary outcomes, numerical rating scale (NRS) for postoperative pain (0-10) was recorded up to 96 h postoperatively, and use of rescue analgesics was evaluated at 6, 24, and 48 h postoperatively. RESULTS: In the ELA, no-ELA, and elective groups, 61, 73, and 88 parturients, respectively, were ultimately enrolled. The NRS for pain were similar among the three groups, except at 6 h postoperatively. Parturients in the no-ELA group demonstrated significantly higher NRS at 6 h postoperatively than those in the ELA group (P = 0.01).More patients in the no-ELA group required rescue analgesics than in the ELA (P = 0.001) and elective groups (P < 0.001) at 6-24 h postoperatively. Moreover, the proportion of patients requiring rescue analgesics ≥2 times was also significantly higher in the no-ELA group (vs. the ELA group, P = 0.004; vs. the elective group, P < 0.001). CONCLUSION: Parturients undergoing emergency C­sec without ELA management during labor experienced greater postoperative pain and a greater use of rescue analgesics during the postoperative period. The findings suggest that administration of ELA before emergency C­sec may act as pre-emptive analgesia against postoperative pain.

Effects of depth of neuromuscular block on surgical conditions during laparoscopic colorectal surgery: a randomised controlled trial.

There have been few objective evaluations of the effects of deep neuromuscular blockade on intra-operative conditions. In this prospective randomised controlled study, we evaluated the effects of deep neuromuscular block on surgical conditions during laparoscopic colorectal surgery. Patients were randomly allocated using a computer-generated randomisation code to either moderate (train-of-four count 1-2 maintained and antagonised with neostigmine) or deep (post-tetanic count 1-2 maintained and reversed with sugammadex) levels of neuromuscular blockade. The primary outcome measure was the number of abrupt increases in intra-abdominal pressure intra-operatively. Secondary outcome variables were intra-operative restoration of spontaneous breathing, number of surgical requests for additional neuromuscular blockade, surgical rating of operating conditions and patient satisfaction. The surgeon who rated the surgical conditions score and investigator who checked the postoperative variables were blinded to patient allocation. In total, we recruited 70 patients of whom 64 (32 in each group) were analysed. Increases in intra-abdominal pressure (14/32 vs. 6/32; p = 0.031), intra-operative restoration of spontaneous breathing (16/32 vs. 2/32; p < 0.001) and request for additional neuromuscular blockade (21/32 vs. 8/32; p = 0.001) were more frequent in the moderate compared with the deep group. In patients undergoing elective laparoscopic colorectal surgery, deep neuromuscular blockade provided better surgical conditions than moderate neuromuscular blockade, as measured by a reduction in the incidence of intra-abdominal pressure alarms.

A Study on CYP2C19 and CYP2D6 Polymorphic Effects on Pharmacokinetics and Pharmacodynamics of Amitriptyline in Healthy Koreans.

We performed a double-blinded, genotype-based stratification study to explore the pharmacokinetics and pharmacodynamics of amitriptyline according to CYP2C19 and CYP2D6 genotype in Korean subjects. Twenty-four healthy adults were grouped by genotype of CYP2C19 and CYP2D6. After a single dose of 25 mg of amitriptyline, blood samples were collected and anticholinergic effects were measured. The extent of N-demethylation of amitriptyline significantly decreased in subjects carrying two nonfunctional alleles of CYP2C19. The extent of hydroxylation of amitriptyline or nortriptyline was significantly reduced in subjects carrying two CYP2D6 decreased functional alleles compared with those with no or one decreased functional allele. The overall metabolic pathway of amitriptyline was more likely to be dominated by CYP2C19 than CYP2D6. The gene variations of CYP2C19 and CYP2D6 did not change the pharmacodynamic effect. The findings of this study will provide useful information on individualized drug treatment with amitriptyline considering both CYP2D6 and CYP2C19 gene variations.

Porphyromonas gingivalis induces autophagy in THP-1-derived macrophages.

Autophagy provides a mechanism for the turnover of cellular organelles and proteins through a lysosome-dependent degradation pathway and is a possible mechanism in inflammatory disease. Periodontitis is an inflammatory disease caused by periodontal pathogens. Porphyromonas gingivalis, an important periodontal pathogen, activates cellular autophagy to provide a replicative niche while suppressing apoptosis in endothelial cells. However, the molecular basis for a causal relationship between P. gingivalis and autophagy is unclear. This research examines the involvement of P. gingivalis in autophagy through light chain 3 (LC3) and autophagic proteins, and the role of P. gingivalis-induced autophagy in the clearance of P. gingivalis and inflammation. To investigate the molecular mechanism of autophagy induced by P. gingivalis, PMA-differentiated THP-1-derived macrophages were infected with live P. gingivalis. The P. gingivalis increased the formation of autophagosomes in a multiplicity of infection-dependent manner, as well as autophagolysosomes. Porphyromonas gingivalis activated LC3-I/LC3-II conversion and increased the conjugation of autophagy-related 5 (ATG5) -ATG12 and the expression of Beclin1. The expressions of Beclin1, ATG5-ATG12 conjugate, and LC3-II were significantly inhibited by the presence of 3-methyladenine, an autophagy inhibitor. Interestingly, 3-methyladenine increased the survival of P. gingivalis and proinflammatory cytokine interleukin-1ß production. The data indicate that P. gingivalis induces autophagy in PMA-differentiated THP-1-derived macrophages and in turn, macrophages eliminate P. gingivalis through an autophagic response, which can lead to the restriction of an excessive inflammatory response by downregulating interleukin-1ß production. The induction of autophagy by P. gingivalis may play an important role in the periodontal inflammatory process and serve as a target for the development of new therapies.

Magnesium sulphate attenuates acute postoperative pain and increased pain intensity after surgical injury in staged bilateral total knee arthroplasty: a randomized, double-blinded, placebo-controlled trial.

BACKGROUND: We evaluated the effect of magnesium sulphate on increased pain in 44 patients undergoing staged bilateral total knee arthroplasty (TKA). METHODS: The magnesium group (n=22) and the control group (n=22) received magnesium sulphate and isotonic saline, respectively, throughout the surgery. Postoperative pain (visual analogue scale, VAS) at rest and the amounts of patient-controlled analgesia (PCA, fentanyl) and rescue analgesia (ketoprofen) administered during the first 48 h were compared between the two groups and within each group between the first and second TKA. RESULTS: The VAS scores were significantly higher in the control group than in the magnesium group not only after the first TKA [29 (11) vs 19 (9) at 24 h and 33 (8) vs 24 (10) at 48 h; P=0.001] but also after the second TKA [44 (17) vs 20 (10) at 24 h and 43 (14) vs 25 (10) at 48 h; P<0.001]. In the control group, VAS scores were significantly higher for the second than for the first operated knee [44 (17) vs 29 (11) at 24 h and 43 (14) vs 33 (8) at 48 h; P<0.001 and P=0.006, respectively]. In the magnesium group, there were no significant differences in VAS scores between the first and second TKA. Magnesium significantly reduced the amounts of rescue analgesics and fentanyl administered over the first 48 h postoperatively. CONCLUSIONS: Magnesium sulphate administration significantly reduced postoperative pain and minimized the difference in pain intensity between the first and second operations. CLINICAL TRIAL REGISTRATION: KCT0001361.

The effect of tranexamic acid on blood coagulation in total hip replacement arthroplasty: rotational thromboelastographic (ROTEM®) analysis.

We evaluated changes in rotational thromboelastometry (ROTEM(®) ) parameters and clinical outcomes in patients undergoing total hip replacement arthroplasty, with concomitant infusions of tranexamic acid and of 6% hydroxyethyl starch 130/0.4. Fifty-five patients were randomly assigned to either the tranexamic acid (n = 29) or the control (n = 26) group. Hydroxyethyl starch was administered in the range of 10-15 ml.kg(-1) during the operation in both groups. In the control group, the clot formation time and maximum clot firmness of APTEM showed significant differences when compared with those of EXTEM at one hour postoperatively, suggestive of fibrinolysis. In the tranexamic acid group, there was no significant difference between each postoperative EXTEM and APTEM parameter. In the tranexamic acid and control group, postoperative blood loss was 308 ml (210-420 [106-745]) and 488 ml (375-620 [170-910], p = 0.002), respectively, and total blood loss was 1168 ml (922-1470 [663-2107]) and 1563 ml (1276-1708 [887-1494], p = 0.003). Haemoglobin concentration was higher in the tranexamic acid group on the second postoperative day (10.5 (9.4-12.1 [7.9-14.0]) vs. 9.6 (8.9-10.5[7.3-16.0]) g.dl(-1) , p = 0.027). In patients undergoing total hip replacement arthroplasty, postoperative fibrinolysis aggravated by hydroxyethyl starch was attenuated by co-administration of 10 mg.kg(-1) tranexamic acid, which may have led to less postoperative blood loss.

The effects of acute normovolaemic haemodilution on peri-operative coagulation in total hip arthroplasty.

Total hip arthroplasty results in substantial blood loss in the peri-operative period. We evaluated the effects of acute normovolaemic haemodilution on blood coagulation and platelet function in 11 patients undergoing total hip arthroplasty. We performed acute normovolaemic haemodilution and haematological tests, rotational thromboelastometry (ROTEM(®) ) and whole-blood impedance aggregometry. Blood samples were obtained at three time points: (i) before the initiation of acute normovolaemic haemodilution; (ii) 20 min after completion of acute normovolaemic haemodilution; and (iii) 20 min after retransfusion. After acute normovolaemic haemodilution, ROTEM parameters demonstrated hypocoagulability. Clot formation time of INTEM was increased by 31.6% (p = 0.016), whereas the α-angle and maximum clot formation of INTEM decreased by 8.1% (p = 0.032) and 3.0% (p = 0.013) respectively, compared with baseline values. Clotting time and clot formation time of EXTEM were increased by 40.8% (p = 0.042) and 31.3% (p = 0.016), respectively, whereas the α-angle and maximum clot formation of EXTEM were decreased by 11.9% (p = 0.020) and 9.5% (p = 0.013), respectively. The maximum clot formation of FIBTEM decreased by 35.1% compared with the baseline value (p = 0.007). Following retransfusion, ROTEM values returned to baseline; clot formation time decreased and the α-angle and maximum clot formation increased. There were no significant changes in platelet aggregation during the study. At 20 min after the end of acute normovolaemic haemodilution, the international normalised ratio of prothrombin time was increased compared with the baseline value (p = 0.003). We conclude that acute normovolaemic haemodilution resulted in a hypocoagulable state compared with baseline values and that coagulation parameters returned to normal after retransfusion.

Effects of magnesium sulphate on coagulation after laparoscopic colorectal cancer surgery, measured by rotational thromboelastometry (ROTEM® ).

We investigated the effects of magnesium sulphate on blood coagulation profiles using rotational thromboelastometry in patients undergoing laparoscopic colorectal cancer surgery. Patients were randomly allocated to the magnesium group (n = 22) or control group (n = 22). The magnesium group received intravenous magnesium sulphate (50 mg.kg(-1) followed by a continuous infusion of 15 mg.kg(-1) .h(-1) ), whereas the control group received the same volume of isotonic saline. Mean (SD) postoperative serum magnesium levels were 1.60 (0.13) mmol.l(-1) in the magnesium group compared with 0.98 (0.06) mmol.l(-1) in the control group (p < 0.001). All maximum clot firmness values of ROTEM analysis were significantly lower on the third postoperative day in the magnesium group compared with the control group (p < 0.05). We conclude that ROTEM analysis demonstrated that intra-operative administration of intravenous magnesium sulphate reduces blood hypercoagulability in patients undergoing laparoscopic colorectal cancer surgery.

Higher operating tables provide better laryngeal views for tracheal intubation.

BACKGROUND: The present study was conducted to investigate the influence of different operating table heights on the quality of laryngeal view and the discomfort of the anaesthetist during enodotracheal intubation. METHODS: Eight anaesthetists participated, to each of whom 20 patients were allocated. Before induction of anaesthesia, the height of the operating table was adjusted to place the patient's forehead at one of four landmarks on the anaesthetist's body (the order being determined by block randomization with eight blocks): umbilicus (Group U), lowest rib margin (Group R), xiphoid process (Group X), and nipple (Group N). Next, the anaesthetist began the laryngoscopy and evaluated the grade of laryngeal view. For this 'initial posture', the anaesthetist was not allowed to adjust his or her posture (flexion or extension of the neck, lower back, knee, and ankle). This laryngeal view was then re-graded after these constraints were relaxed. At each posture, the anaesthetist's joint movements and discomfort during mask ventilation or intubation were evaluated. RESULTS: The laryngeal view before postural changes was better in Group N than in Group U (P=0.003). The objective and subjective measurements of neck or lower back flexion during intubation were higher in Group U than in Groups X and N (P<0.01 for each). The improvement of laryngeal view resulting from postural changes correlated with the anaesthetist's discomfort score before the postural change (P<0.01). CONCLUSIONS: Higher operating tables (at the xiphoid process and nipple level of the anaesthetist) can provide better laryngeal views with less discomfort during tracheal intubation. TRIAL REGISTRY NUMBER: NCT01649973 (clinicaltrials.gov).

Emergence agitation in children undergoing adenotonsillectomy: a comparison of sevoflurane vs. sevoflurane-remifentanil administration.

BACKGROUND: Sevoflurane is widely used in paediatric anaesthesia but frequently causes emergence agitation (EA). This study evaluated whether limiting the sevoflurane concentration by combining remifentanil with sevoflurane reduced the incidence of EA. METHODS: Eighty-four preschool children scheduled for adenotonsillectomy were randomly assigned to either the remifentanil or sevoflurane group. In the remifentanil group, anaesthesia was induced with thiopental, rocuronium, and 1% sevoflurane. It was maintained with 1% sevoflurane, 60% nitrous oxide in oxygen, and a continuous infusion of remifentanil. For the sevoflurane group, anaesthesia was induced with thiopental, rocuronium, and 8% sevoflurane, and was maintained with 2-3% sevoflurane. Both groups received ketorolac 1 mg/kg and dexamethasone 0.15 mg/kg. EA was measured using the paediatric anaesthesia emergence delirium (PAED) scale and a four-point EA scale in the post-anaesthesia care unit. RESULTS: The scores on the PAED scales were significantly lower in the remifentanil group than in the sevoflurane group [median (interquartile range); 6 (4.25-10.25) vs. 11 (7.75-14.0), P = 0.007], and the proportion of patients with PAED scores ≥ 10 was significantly lower in the remifentanil group than in the sevoflurane group [15 (35.7%) vs. 27 (64.2%), P = 0.009]. The incidence of EA evaluated using the four-point scale was also lower in the remifentanil group [11 (26.1%) vs. 21 (50%), respectively, P = 0.025]. CONCLUSION: The incidence of EA was lower in children undergoing adenotonsillectomy who received a lower concentration of sevoflurane combined with remifentanil than in those given a higher concentration of sevoflurane without remifentanil.

Effects of magnesium sulphate on postoperative coagulation, measured by rotational thromboelastometry (ROTEM(®)).

We investigated the effects of magnesium sulphate on blood coagulation profiles using rotational thromboelastometry in gynaecological patients undergoing pelviscopic surgery. Patients were randomly allocated to the magnesium group (n = 20) or control group (n = 20). The magnesium group received magnesium sulphate (50 mg.kg(-1) followed by continuous infusion of 15 mg.kg(-1).h(-1)), whereas the control group received the same volume of isotonic saline according to the same methods. Mean (SD) postoperative serum magnesium levels were 1.58 (0.17) mmol.l(-1) in the magnesium group compared with 0.98 (0.06) mmol.l(-1) in the control group (p < 0.001). Postoperative clotting time, clot formation time, α-angle and maximum clot firmness of INTEM, and clot formation time, α-angle, and maximum clot firmness of EXTEM were significantly different between the two groups (p < 0.05). Intra-operative infusion of magnesium sulphate seems to attenuate postoperative hypercoagulability by maintaining magnesium levels at the upper limit of the normal range.

Tumor necrosis factor-α and interleukin-1ß expression pathway induced by Streptococcus mutans in macrophage cell line RAW 264.7.

Streptococcus mutans, a major etiological agent of dental caries, frequently causes systemic disease, such as subacute bacterial endocarditis, if it enters the bloodstream. In this study, the production pathways of the proinflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), induced by S. mutans in mouse macrophage were examined using a quantitative real-time polymerase chain reaction and an enzyme-linked immunosorbent assay. The S. mutans stimulated the expression of TNF-α and IL-1ß mRNA at a multiplicity of infection of 1 : 100, which increased at 2 and 4 h, respectively, to 24 h. It also induced the production of high levels of the TNF-α and IL-1ß proteins, which increased at 2 h and reached a peak at 4 and 24 h, respectively. Nuclear factor-κB (NF-κB) was activated and reached a maximum level 30 min after the S. mutans treatment. The expression of TNF-α and IL-1ß mRNA and protein was suppressed by the treatment with pyrrolidine dithiocarbamate, an NF-κB inhibitor. The S. mutans-induced TNF-α expression was suppressed by the presence of SB203580, a p38 mitogen-activated protein (MAP) kinase inhibitor, or SP600125, a Jun N-terminal kinase (JNK) MAP kinase inhibitor. On the other hand, IL-1ß expression was inhibited by extracellular signal-regulated kinase (ERK)/p38/JNK MAP kinase inhibitor pretreatment. In addition, TNF-α production was suppressed more in the Toll-like receptor 2(-/-) (TLR2(-/-)) macrophages than in the TLR4(-/-) macrophages, whereas IL-1ß production was suppressed more in the TLR4(-/-) macrophages than in the TLR2(-/-) macrophages. These results show that S. mutans stimulates the production of TNF-α and IL-1ß in the mouse macrophage cell line, RAW 264.7, by activating ERK/p38/JNK, and NF-κB through TLR2 and TLR4, respectively.

Influence of a prolonged lateral position on induction of spinal anesthesia for cesarean delivery: a randomized controlled trial.

BACKGROUND: Maternal hypotension occurs commonly during cesarean delivery under spinal anesthesia. We evaluated whether hypotension due to aortocaval compression could be prevented by maintaining a lateral position after an intrathecal injection. METHODS: Eighty-six women undergoing elective cesarean delivery were enrolled. Spinal anesthesia was conducted in the right lateral position using 8 mg of hyperbaric bupivacaine and 15 µg of fentanyl. Patients were randomly assigned to maintain the right lateral position for 6 min before assuming the wedged supine position (group L), or to assume the wedged supine position immediately after the spinal injection (group S). Hypotension was defined as a decrease in mean arterial pressure to <80% of baseline. Ephedrine was given if blood pressure decreased to <70% of baseline. The incidence of hypotension and nausea, ephedrine requirement, maximal block height, and neonatal outcomes were evaluated. RESULTS: No significant between-group differences were observed in the lowest blood pressure, total ephedrine dose, or incidence of hypotension or nausea. Onset of hypotension was delayed (6 ± 2 vs. 10 ± 3 min, P<0.001), and the sensory block level was more cephalad in group L than in group S (T2 [C8-T5] vs. T4 [T1-T6], P=0.001). Apgar scores did not differ between the groups. CONCLUSION: During spinal anesthesia for elective cesarean delivery, maintaining the lateral position for 6 min after an intrathecal injection of hyperbaric bupivacaine resulted in a more gradual and higher cephalad sensory block, without an increase in the incidence of maternal hypotension.

Drug-administration sequence of target-controlled propofol and remifentanil influences the onset of rocuronium. A double-blind, randomized trial.

BACKGROUND: Remifentanil is known to cause bradycardia and hypotension, as well as the decreases of cardiac output (CO). We hypothesized that hemodynamic suppression by remifentanil would affect the onset time of rocuronium. This study investigated whether the onset of rocuronium was influenced by the drug-administration sequence during induction of anesthesia with target-controlled infusion of propofol and remifentanil. METHODS: Healthy adult patients (n = 126) undergoing elective surgery under general anesthesia were randomized into two groups according to drug-administration sequence. In Remi-Pro-Rocu group (n = 62), remifentanil was infused first, followed by propofol. Then, rocuronium was administered lastly. In Pro-Rocu-Remi group (n = 64), propofol, rocuronium, and remifentanil were given in that order. As a primary outcome, the onset time of rocuronium was measured. Mean arterial pressure (MAP), heart rate (HR), CO, and stroke volume were recorded before anesthesia (T1), at injection of rocuronium (T2), immediately before and after intubation (T3 and T4). RESULTS: In Remi-Pro-Roc group, the onset of rocuronium was delayed significantly compared with Pro-Rocu-Remi group [median (interquartile range); 130 (105-150) vs. 90 (71-100) s, P < 0.001]. At the time of rocuronium injection (T2), MAP, HR, and CO were significantly lower in Remi-Pro-Rocu group than Pro-Rocu-Remi group (P < 0.001). CONCLUSION: The onset time of rocuronium is prolonged significantly by early administration of remifentanil during target-controlled infusion of propofol and remifentanil, and it may be due to the decreased CO caused by remifentanil.

Comparison of inflammatory microRNA expression in healthy and periodontitis tissues

MicroRNAs (miRNAs) are short RNA molecules that negatively regulate gene expression primarily by degrading target mRNA or inhibit the translation of protein product. Recently, many reports have shown the altered miRNA expression in various diseases. However, there are no reports on miRNA expression related to periodontitis. Thus, this study aimed to compare the miRNAs differentially expressed in healthy and chronic periodontitis tissues and to determine the miRNAs closely associated with chronic periodontitis. To find out the miRNAs differentially induced in healthy and chronic periodontitis tissues, miRNA microarray was carried out and the expression of miRNAs was confirmed by real-time PCR. According to miRNA microarray analyses, six miRNA genes, let-7a, let-7c, miR-130a, miR301a, miR-520d, and miR-548a, were up-regulated more than 8 fold compared to the healthy gingiva. The expression of twenty-two miRNAs was increased more than 4 fold. Among these miRNAs, eight miRNAs which are known to be closely related to inflammation were selected. Six of these miRNA genes, miR-181b, miR-19b, miR-23a, miR-30a, miR-let7a, and miR-301a, were amplified successfully and increased much more in periodontitis gingivae than in healthy ones. In summary, this study indicate that six miRNAs up-regulated in periodontitis gingiva may play a key role in chronic periodontitis

Comparison of inflammatory microRNA expression in healthy and periodontitis tissues

MicroRNAs (miRNAs) are short RNA molecules that negatively regulate gene expression primarily by degrading target mRNA or inhibit the translation of protein product. Recently, many reports have shown the altered miRNA expression in various diseases. However, there are no reports on miRNA expression related to periodontitis. Thus, this study aimed to compare the miRNAs differentially expressed in healthy and chronic periodontitis tissues and to determine the miRNAs closely associated with chronic periodontitis. To find out the miRNAs differentially induced in healthy and chronic periodontitis tissues, miRNA microarray was carried out and the expression of miRNAs was confirmed by real-time PCR. According to miRNA microarray analyses, six miRNA genes, let-7a, let-7c, miR-130a, miR301a, miR-520d, and miR-548a, were up-regulated more than 8 fold compared to the healthy gingiva. The expression of twenty-two miRNAs was increased more than 4 fold. Among these miRNAs, eight miRNAs which are known to be closely related to inflammation were selected. Six of these miRNA genes, miR-181b, miR-19b, miR-23a, miR-30a, miR-let7a, and miR-301a, were amplified successfully and increased much more in periodontitis gingivae than in healthy ones. In summary, this study indicate that six miRNAs up-regulated in periodontitis gingiva may play a key role in chronic periodontitis