Dexmedetomidine attenuates ferroptosis by Keap1-Nrf2/HO-1 pathway in LPS-induced acute kidney injury.

Previous research has demonstrated that Dexmedetomidine (DEX), an α2 adrenergic agonist commonly used for its sedative and analgesic properties, can attenuate lipopolysaccharide (LPS)-induced acute kidney injury (AKI). This study explores the possibility that DEX's protective effects in LPS-induced AKI are mediated through the inhibition of ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation, and the activation of the antioxidant response through the Keap1/Nrf2/HO-1 signaling pathway. We induced AKI in 42 mice using LPS and divided them into six groups: saline control, LPS, LPS + DEX, LPS + Ferrostatin-1 (LPS + Fer-1; a ferroptosis inhibitor), LPS + DEX with α2-receptor antagonist Altipamizole (LPS + DEX + ATI), and LPS + DEX with Nrf2 inhibitor ML385 (LPS + DEX + ML385). After 24 h, we analyzed blood and kidney tissues. LPS exposure resulted in AKI, with increased serum creatinine, BUN, and cystatin C, and tubular damage, which DEX and Fer-1 ameliorated. However, Altipamizole and ML385 negated these improvements. The LPS group exhibited elevated oxidative stress markers and mitochondrial damage, reduced by DEX and Fer-1, but not when α2-adrenergic or Nrf2 pathways were blocked. Nrf2 and HO-1 expression declined in the LPS group, rebounded with LPS + DEX and LPS + Fer-1, and fell again with inhibitors; inversely, Keap1 expression varied. Our results demonstrate that DEX may protect against LPS-induced AKI, at least partially by regulating ferroptosis and the α2-adrenergic receptor/Keap1/Nrf2/HO-1 pathway, suggesting a potential therapeutic role for DEX in AKI management by modulating cell death and antioxidant defenses.

Analysis of immune response in BALB/c mice immunized with recombinant plasmids pMZ-X3-Ts14-3-3.3 and pMZ-X3-sp-Ts14-3-3.3 of Taenia solium.

There is a lack of vaccine against human cysticercosis, thus making a huge population at the risk of infection. In this study, we chose a novel potential antigen molecule Taenia solium 14-3-3.3 (Ts14-3-3.3) and optimized it as sp-Ts14-3-3.3 (sp is immunoglobulin H chain V-region precursor, partial) in order to construct recombinant plasmids pMZ-X3-Ts14-3-3.3 and pMZ-X3-sp-Ts14-3-3.3. BALB/c mice were divided into four groups for immunization: pMZ-X3-Ts14-3-3.3, pMZ-X3-sp-Ts14-3-3.3, pMZ-X3 plasmid control group and PBS control group. Compared with two control groups, the proliferation level of splenic lymphocytes increased significantly in pMZ-X3-Ts14-3-3.3 and pMZ-X3-sp-Ts14-3-3.3 groups and reached the maximum in week 6. And the same case arose as cytokines associated with Th1 response, IFN-γ, and IL-2 while those with Th2 response, IL-4, IL-10 went up and reached the maximum in week 4. The levels of serum specific IgG, IgG1 and IgG2a rose and reached the maximum in week 6, 4 and 6, respectively. Meanwhile, the proportion of CD4+/CD8+ splenic T lymphocytes increased and reached the peak in week 6. The results indicated that the recombinant plasmids pMZ-X3-Ts14-3-3.3 and pMZ-X3-sp-Ts14-3-3.3 can induce specific cellular and humoral immune responses in BALB/c mice with immunization. Notably, the recombinant plasmid pMZ-X3-sp-Ts14-3-3.3 has a better immune effect, which proves that Ts14-3-3.3 enjoys a higher possibility as a potential antigen molecule to T. solium vaccine.

Analysis of Immune Responses in Mice Orally Immunized with Recombinant pMG36e-SP-TSOL18/Lactococcus lactis and pMG36e-TSOL18/Lactococcus lactis Vaccines of Taenia solium.

Cysticercosis is a cosmopolitan zoonotic parasitic disease infected by larval of Taenia solium (T. solium). Several drugs for the treatment of cysticercosis, such as praziquantel, albendazole, and mebendazole, have certain toxicity and side effects. Considering that there is no vaccine available, we studied a new vaccine for cysticercosis in this study. The complete TSOL18 gene and the optimized SP-TSOL18 gene fragments were obtained using PCR-based accurate synthesis method. The secretory and intracellular recombinant pMG36e-SP-TSOL18/Lactococcus lactis (L. lactis) and pMG36e-TSOL18/L. lactis vaccines of T. solium were prepared. Immune responses in mice orally immunized with these two recombinant L. lactis vaccines were analyzed by the determination of specific antibodies (IgG, IgG1, IgG2a, and sIgA) in serum, spleen lymphocyte proliferation, and cytokines (IL-2, IFN-γ, IL-4, and IL-10) in spleen lymphocyte culture supernatant. Our results showed that, after the first immunization, in these two recombinant L. lactis vaccine groups, the levels of serum specific IgG, IgG2a, and IgG1 increased on 14-56 d and reached the highest level on days 42, 42, and 28, respectively. The level of specific sIgA of intestinal mucosa also increased on 14-56 d and reached the highest level on day 42. The level of spleen lymphocyte proliferation increased on 14-56 d and reached the highest level on day 42. The levels of IL-2, IFN-γ, IL-4, and IL-10 in spleen lymphocyte culture supernatant increased on 14-56 d and reached the highest level on days 42, 42, 28, and 28, respectively. These results indicated that the recombinant pMG36e-SP-TSOL18/L. lactis and pMG36e-TSOL18/L. lactis vaccines can induce specific cellular, humoral, and mucosal immune responses in mice with oral vaccination. More importantly, the recombinant pMG36e-SP-TSOL18/L. lactis vaccine has a better immune effect. In summary, these results demonstrated the possibility of using L. lactis strain as a vector to deliver protective antigens of T. solium.

SIRT1 plays a neuroprotective role in traumatic brain injury in rats via inhibiting the p38 MAPK pathway.

Traumatic brain injury (TBI) is a major cause of disability and death in patients who experience a traumatic injury. Mitochondrial dysfunction is one of the main factors contributing to secondary injury in TBI-associated brain damage. Evidence of compromised mitochondrial function after TBI has been, but the molecular mechanisms underlying the pathogenesis of TBI are not well understood. Silent information regulator family protein 1 (SIRT1), a member of the NAD+-dependent protein deacetylases, has been shown to exhibit neuroprotective activities in animal models of various pathologies, including ischemic brain injury, subarachnoid hemorrhage and several neurodegenerative diseases. In this study, we investigated whether SIRT1 also exert neuroprotective effect post-TBI, and further explored the possible regulatory mechanisms involved in TBI pathogenesis. A lateral fluid-percussion (LFP) brain injury model was established in rats to mimic the insults of TBI. The expression levels of SIRT1, p-p38, cleaved caspase-9 and cleaved caspase-3 were all markedly increased and reached a maximum at 12 h post-TBI. In addition, mitochondrial function was impaired, evidenced by the presence of swollen and irregularly shaped mitochondria with disrupted and poorly defined cristae, a relative increase of the percentage of neurons with low ΔΨm, the opening of mPTP, and a decrease in neuronal ATP content, especially at 12 h post-TBI. Pretreatment with the SIRT1 inhibitor sirtinol (10 mg/kg, ip) induced p-p38 activation, exacerbated mitochondrial damage, and promoted the activation of the mitochondrial apoptosis pathway. In contrast, pretreatment with the p38 inhibitor SB203580 (200 µg/kg, ip) significantly attenuated post-TBI-induced expression of both cleaved caspase-9 and cleaved caspase-3 and mitochondrial damage, whereas it had no effects on SIRT1 expression. Together, these results reveal that the 12 h after TBI may be a crucial time at which secondary damage occurs; the activation of SIRT1 expression and inhibition of the p38 MAPK pathway may play a neuroprotective role in preventing secondary damage post-TBI. For this reason, both SIRT1 and p38 are likely to be important targets to prevent secondary damage post-TBI.

[Changes of superoxide dismutase and lipid peroxide in rats with Pneumocystis carinii pneumonia].

Sprague-Dawley (SD) rat model of Pneumocystis carinii pneumonia (PCP) was established by groin subcutaneous injection with dexamethasone sodium phosphate 35 mg each twice a week for eight weeks. There were two groups: infected group (eighteen rats) and normal control group (six rats) . Pathological changes in lung tissues were observed in the lung imprint after staining with Gomori methenamine silver (GMS) and in tissue sections after staining with hematoxylin-eosin (HE). The activity of superoxide dismutase (SOD) and the content of lipid peroxide (LPO) in lung tissue homogenate were detected by spectrophotometric method. Results showed that in infected group more PC cysts were found in the lung imprint and typical pathological change observed in the lung section. SOD activity in infected group [(31.49 +/- 7.18) U/mgprot] decreased significantly compared with the control [(54.41 +/- 8.97) U/mgprot] (P < 0.01), but LPO in infected group [(2.26 +/- 0.21) nmol/mgprot] was higher significantly than the control [(1.63 +/- 0.01) nmol/mgprot] (P < 0.01).

[Changes of spleen cytokines in mice immunized with recombinant Bb-Eg95-EgA31 vaccine against Echinococcus granulosus].

OBJECTIVE: To investigate the level of cytokines in spleen from mice immunized with recombinant Bifidobacteria bifidum(Bb)-Eg95-EgA31 vaccine of Echinococcus granulosus (Eg) and challenged with Eg protoscoleces. METHODS: 56 female BALB/c mice were randomly divided into 7 groups: Recombinant Bb-Eg9S-95-EgA31 vaccine subcutaneous injection (group A), intramuscular injection (B), intranasal immunization (C), oral administration (D), blank vector control (E), Bb control (F) and MRS control (G). Mice in all groups were challenged with 50 Eg protoscoleces on the 8th week after vaccination and sacrificed on the 25th week after infection. Spleens were collected to prepare splenocytes, which were cultured under activation of crude Eg antigen (EgAg), with concanavalin A (ConA) or lipopolysaccharide (LPS) stimulation and non-stimulation as control. The splenocyte supernatants were collected to determine the levels of interferon-gamma (IFN-gamma), interleukin-12 (IL-12), tumour necrosis factor-alpha (TNF-alpha) and IL-10 by ELISA. RESULTS: The level of IFN-gamma in groups A [(137.5 +/- 23.2) pg/ml], B [(162.5 +/- 23.2) pg/ml], C [(250.0 +/- 53.5) pg/ml] and D [(215.0 +/- 37.4) pg/ml] was higher than that of group G [(50.0 +/- 10.7) pg/ml] (P < 0.01). The level of IL-12 in groups A [(27.5 +/- 4.6) pg/ml], B [(32.5 +/- 4.6) pg/ml], C [(45.0 +/- 5.4) pg/ml] and D [(35.0 +/- 5.4) pg/ml] was higher than that of group G [(15.0 +/- 5.4) pg/ml] (P < 0.01). The level of TNF-alpha in groups A [(275.0 +/- 46.3) pg/ml], B [(325.0 +/- 46.3) pg/ml], C [(450.0 +/- 53.5) pg/ml] and D [(350.0 +/- 53.5) pg/ml] was higher than that of group G [(150.0 +/- 53.5) pg/ml] (P < 0.01). The level of IL-10 in groups A [(37.5 +/- 4.6) pg/ml], B [(35.0 +/- 5.4) pg/ml], C [(25.0 +/- 5.4) pg/ml] and D [(32.5 +/- 4.6) pg/ml] was lower than that of group G [(45.0 +/- 5.4) pg/ml] (P < 0.05 or P < 0.01). CONCLUSION: The recombinant Bb-Eg95-EgA31 vaccine can induce a protective Th1 type immune response in mice

[Research status on DNA vaccine against Cysticercus cellulosae infection].

DNA vaccine against Cysticercus cellulosae infection is a newly emerging vaccine in recent years. It can induce not only humoral immune response, but also a high level cellular immune response. The DNA vaccine displays prominent advantages in the prevention on cysticercosis. This article reviews the current situation on several DNA vaccines.

[Inhibition on apoptosis of splenocytes in infected mice by immunization with recombinant Bb-Eg95-EgA31 protein of Echinococcus granulosus].

OBJECTIVE: To investigate the weight reduction of hydatid cysts and apoptosis of splenocytes in infected mice by recombinant Bifidobacteria bifidum (Bb)-Eg95-EgA31 protein of Echinococcus granulosus (Eg) and challenged with Eg protoscoleces. METHODS: 56 female BALB/c mice were randomly divided into 7 groups. Groups A and B were injected subcutaneously and intramuscularly respectively with 5 x 10(6) colony-forming unit (CFU) recombinant Bb-Eg95-EgA31 protein, group C was immunized intranasally by 5 x 10(5) CFU protein, group D was vaccinated transgastrically by 5 x 10(8) CFU protein, groups E and F were injected subcutaneously with 5 x 10(6) CFU blank vector [Bb (pGEX-1 lambda T)] and Bb respectively, and group G was injected subcutaneously with 100 microl MRS. Mice in all groups were challenged with 50 Eg protoscoleces on the 8th week after vaccination and sacrificed on the 25th week after infection. The weight of hydatid cysts was measured and weight-reduction rate was calculated. Spleens were collected to prepare splenocytes which were cultured under stimulation with concanavalin A (ConA). The apoptotic rate was determined by flow cytometry (FCM). RESULTS: The average weight of hydatid cysts in groups A [(41.0 +/- 23.0) mg], B [(44.0 +/- 22.0) mg], C [(22.0 +/- 21.0) mg], and D [(28.0 +/- 16.0) mg] was lower than that of group G [(75.0 +/- 33.0) mg] (P<0.05, P<0.01), and there was no significant difference among groups A, B, C and D (P>0.05); no significant difference was found between group G and groups E [(63.0 +/- 30.0) mg], F [(69.0 +/- 22.0) mg] (P>0.05). The apoptotic rate of splenocytes cultured with no ConA in groups A (0.14 +/- 0.01), B (0.14 +/- 0.01), C (0.13 +/- 0.01), and D (0.141 +/- 0.01) was lower than that of group G (0.21 +/- 0.01) (P<0.05); that of group C was lower than groups A, B, and D (P<0.05); there was no significant difference between groups D and A, between groups A and B, and between groups E (0.20 +/- 0.01), F (0.20 +/- 0.01) and group G. The apoptotic rate of splenocytes cultured with ConA in group A (0.19 +/- 0.01), B (0.20 +/- 0.00), C (0.17 +/- 0.01), and D (0.19 +/- 0.01) were lower than that of group G (0.26 +/- 0.01) (P<0.01), that of group C was lower than groups A and B (P<0.01), group C was lower than group D (P<0.05), group D was lower than group B (P<0.05); there was no significant difference between groups A and B, and between groups A and D, and between groups E (0.25 +/- 0.01), F (0.25 +/- 0.01), and group G (P>0.05). The apoptotic rate of splenocytes cultured with ConA was higher than those cultured without ConA (P<0.01). CONCLUSIONS: Apoptosis of splenocytes may be induced by infection of Echinococcus granulosus protoscoleces in mice, while the recombinant Bb-Eg95-EgA31 protein may inhibit the apoptosis of splenocytes in mice challenged with Eg, and induce certain protective immunity in the host.

[Dynamic observation on immune responses in mice administrated with a recombinant Bb-Eg95-EgA31 vaccine of Echinococcus granulosus].

AIM: To dynamically observe the immune responses in mice administrated with a recombinant Bifidobacteria bifidum (Bb)-Eg95-EgA31 vaccine of Echinococcus granulosus. METHODS: BALB/c mice were immunized orally or intranasally by the vaccine. At indicated times after vaccination, the levels of serum IgG, IgG subclass and IgE were determined by ELISA. The levels of IL-12, IFN-gamma, TNF-alpha and IL-10 were measured by ELISA in the supernatant of cultured splenocytes. Proliferation of splenocytes was tested by MTT. The percentage of spleen CD4+ and CD8+ cells was determined by flow cytometry(FCM). RESULTS: The orally immunized mice achieved IgG and IgG3 peaks on 8th week post vaccination, IgG2a peak on 2nd week, IgG2b and IgG1 peaks on 6th week, and IgE peak on 10th week. IFN-gamma and TNF-alpha reached highest level on 4th week, IL-12 on 2nd week, and IL-10 on 6th week. Splenocytes proliferated fastest on 6th week. The percentage of CD4+ cells was peaked on 6th week, while the percentage of CD8+ cells had no obvious change. The intranasally immunized group achieved peaks of IgG, IgG2b and IgE on 10th week, IgG2a peak on 6th week, and peaks of IgG1 and IgG3 on 8th week. IFN-gamma and IL-12 reached highest level on 2nd week, TNF-alpha on 4th week, and IL-10 on 8th week. Splenocytes proliferated fastest on 6th week. The percentage of CD4+ cells was peaked on 6th week, while the percentage of CD8+ cells had no obvious change. CONCLUSION: The recombinant Bb-Eg95-EgA31 vaccine of Echinococcus granulosus induced effective immune responses in mice by either oral vaccination or intranasal inoculation. Our data showed the better immunogenicity of oral vaccination.

[Dynamic observation on splenocyte subsets in mice immunized with recombinant Bb-Eg95-EgA31 vaccine of Echinococcus granulosus].

OBJECTIVE: To dynamically observe changes of subsets of splenocytes in mice immunized with recombinant Bifidobacteria bifidum (Bb)-Eg95-EgA31 vaccine of Echinococcus granulosus (Eg). METHODS: BALB/c mice were vaccinated by 5 x 10(8) colony forming unit (CFU) orally and 5 x 10(5) CFU intranasally respectively. Mice were killed on week 0, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 after immunization respectively, and spleens were separated for cell preparation. CD4+ and CD8+ T cells were determined by flow cytometry (FCM), with MRS as control. RESULTS: In the oral immunization group, CD4+ cells showed a significant increase during the 4th-10th week after vaccination, and reached the highest level on the 6th week, whereas no obvious changes in CD8+ cells numbers were observed. In the intranasal immunization group, CD4+ cells showed an obvious increase during the 4th-8th week after vaccination, and reached the highest level on the 6th week, CD8+ subsets had no obvious changes. CONCLUSION: CD4+ T cell cells may play a key role in immune response in mice immunized with the recombinant Bb-Eg95-EgA31 vaccine of Echinococcus granulosus.

[Influence of baicalin on TNF-alpha and soluble intercellular adhesion molecule-1 in rats infected with Pneumocystis carinii].

OBJECTIVE: To explore the effect of baicalin on tumour necrosis factor-alpha (TNF-alpha) and soluble intercellular adhesion molecule-1 (sICAM-1) of immunosuppressed rats infected with Pneumocystis carinii. METHODS: Forty-nine SD rats were randomly divided into 7 groups: normal control (A), immunosuppressed control (B), SMZ/TMP control (C), baicalin prevention (D), low dose (E), moderate dose (F) and high dose (G). Rats of group D received six injections at three-day intervals with 3.5 mg dexamethasone sodium phosphate for 3 weeks, while groups B, C, E, F and G received same immunosuppressor but for 6 weeks. Rats in group D were given 100 mg/kg baicalin daily for 5 weeks, and groups C, E, F and G were given 250 mg/kg SMZ+50 mg/kg TMP, low dose [100mg/(kg x d)], moderate dose [200 mg/(kg x d)], and high dose [400 mg/(kg x d)] baicalin daily for 2 weeks, respectively. At the end of 8th week after immunosuppression, the contents of TNF-alpha and sICAM-1 in peripheral blood were detected by radioimmunoassay (RIA) and ELISA, respectively. The pathological change of lung was observed by lung imprint smear with gomori methenamine silver (GMS) staining and lung section with hematoxylin-eosin (HE) staining. RESULTS: The content of TNF-alpha in group D [(2.14 +/- 0.14) ng/ml], group E [(2.57 +/- 0.15) ng/ml], group F [(1.46 +/- 0.14) ng/ml], group G [(1.12 +/- 0.13) ng/ml] and group C [(1.59 +/- 0.14) ng/ml] were higher than that of group A [(0.70 +/- 0.21) ng/ml] (P < 0.05, P < 0.01), and lower than group B [(3.65 +/- 0.73) ng/ml] (P < 0.01). The content of sICAM-1 in group D [(618.68 +/- 52.42) pg/ml], group E [(814.29 +/- 61.11) pg/ml], group F [(498.08 +/- 32.56) pg/ml], group G [(377.06 +/- 56.56) pg/ml] and group C [(386.95 +/- 44.98) pg/ml] were lower than group B [(1 247.39 +/- 288.57) pg/ml] (P < 0.05). Compared with immunosuppressed control group, there were less alveolar interstitial lymphocytes, foamy intra-alveolar exudate and inflammation of lung tissue in rats of drug treatment groups. CONCLUSION: Baicalin can decrease the contents of TNF-alpha and sICAM-1, and alleviate inflammation in lung tissues of rats infected with Pneumocystis carinii.

[Research progress in antigens for the diagnosis of alveolar echinococcosis].

Specific antigens of Echinococcus multilocularis is essential for the diagnosis of alveolar echinococcosis and vaccine development. Because of the limited source of nature antigen, its application is restricted. The development of recombinant antigens can provide large amount of antigen under effective quality control. This review summarizes the recent progress in antigen research, especially the recombinant antigen used for diagnosis of the disease.