Effects of prolonged peri-neural bupivacaine infusion in rat sciatic nerves (axon and myelin)

2021 ◽  
pp. 1-10
Author(s):  
John T. Butler ◽  
Tobias J. Robinson ◽  
Jared R. Edwards ◽  
Marjorie R. Grafe ◽  
Jeffrey R. Kirsch

Background/Objective: Peripheral-nerve blocks (PNBs) using continuous-infusion of local anesthetics are used to provide perioperative analgesia. Yet little research exists to characterize the histopathological effects of continuous long-duration PNBs. Herein we test the hypothesis that continuous peri-neural bupivacaine infusion (3-day vs. 7-day infusion) contributes to histologic injury in a duration-dependent manner using an in vivo model of rat sciatic nerves. Methods: We placed indwelling catheters in 22 rats for infusion with low-dose (0.5mg/kg/hr) bupivacaine or normal saline proximal to the right sciatic nerves for 3 or 7 consecutive days. Hind-limb analgesia was measured using Von-Frey nociceptive testing. At infusion end, rats were sacrificed, bilateral nerves were sectioned and stained with hematoxylin and eosin and CD68 for evaluation of inflammatory response, and eriochrome to assess damage to myelin. Results: Animals receiving continuous infusion of bupivacaine maintained analgesia as demonstrated by significant decrease (50%on average) in nociceptive response in bupivacaine-infused limbs across time points. Both 7-day saline and bupivacaine-infused sciatic nerves showed significantly-increased inflammation by H&E staining compared to untreated native nerve controls (P = 0.0001, P <  0.0001). Extent of inflammation did not vary significantly based on infusate (7-day saline vs. 7-day bupivacaine P >  0.99) or duration (3-day bupivacaine vs 7-day bupivacaine P >  0.99). No significant change in sciatic nerve myelin was found in bupivacaine-infused animals compared to saline-infused controls, regardless of duration. Conclusions: Long-duration (7-day) bupivacaine infusion provided durable post-operative analgesia, yet contributed to equivalent neural inflammation as short duration (3-day) infusion of bupivacaine or saline with no evidence of demyelination.

Toxins ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 455 ◽  
Author(s):  
XuanLi Liu ◽  
Michel J Roux ◽  
Serge Picaud ◽  
Daniel Keller ◽  
Arnaud Sauer ◽  
...  

: Panton-Valentine leukocidin (PVL) retinal intoxication induces glial activation and inflammatory response via the interaction with retinal neurons. In this study, rabbit retinal explant was used as a model to study neuronal and glial consequences of PVL intoxication. Retinal explants were treated with different concentrations of PVL. PVL location and neuronal and glial changes were examined using immunohistochemistry. Some inflammatory factors were quantified using RT-qPCR at 4 and 8 h. These results were compared with those of control explants. PVL co-localized rapidly with retinal ganglion cells and with horizontal cells. PVL induced Müller and microglial cell activation. Retinal structure was altered and some amacrine and microglial cells underwent apoptosis. Glial activation and cell apoptosis increased in a PVL concentration- and time-dependent manner. IL-6 and IL-8 expression increased in PVL-treated explants but less than in control explants, which may indicate that other factors were responsible for glial activation and retinal apoptosis. On retinal explants, PVL co-localized with neuronal cells and induced glial activation together with microglial apoptosis, which confirms previous results observed in in vivo model. Rabbit retinal explant seems to be suitable model to further study the process of PVL leading to glial activation and retinal cells apoptosis.


Author(s):  
Edrees Khan Rahmatzada ◽  
Prof. Paras Nath Yadav ◽  
Dr. Yuba Raj Pokharel

Thiosemicarbazone have the antiviral, antibacterial, antifungal, and anticancer effects. 3-OH-Me-TSC inhibited the cell viability of HepG-2 cells by CV assay in a concentration dependent manner (control, 1μM, 3μM, 10μM, 30μM, and 100μM) with IC50 value of 9.587622μM. Further colony formation assay demonstrated that 3-OH-Me-TSC inhibits colony number and size of HepG-2. Wound healing assay exhibited that 3-OH-Me-TSC inhibit the migration of HepG-2 cells. DAPI staining showed that 3-OH-Me-TSC inhibited proliferation of HepG-2 cells in 30μM and 100μM concentrations respectively. 3-OH-Me-TSC inhibited VEGF, p38 alpha, C-JUN, BECN-1, ERK, NF-KB, in HepG-2 cells. We found that 3-OH-Me-TSC inhibit proliferation of HepG-2 cells by inhibiting MAPK signaling pathway, 3-OH-Me-TSC can be developed as future chemotherapeutic agent for treatment of hepatocellular carcinoma after the evaluation of this compounds in more cancer cells an in vivo model.


2020 ◽  
Vol 21 (6) ◽  
pp. 2063
Author(s):  
Mooud Amirkavei ◽  
Marja Pitkänen ◽  
Ossi Kaikkonen ◽  
Kai Kaarniranta ◽  
Helder André ◽  
...  

The induction of heat shock response in the macula has been proposed as a useful therapeutic strategy for retinal neurodegenerative diseases by promoting proteostasis and enhancing protective chaperone mechanisms. We applied transpupillary 1064 nm long-duration laser heating to the mouse (C57Bl/6J) fundus to examine the heat shock response in vivo. The intensity and spatial distribution of heat shock protein (HSP) 70 expression along with the concomitant probability for damage were measured 24 h after laser irradiation in the mouse retinal pigment epithelium (RPE) as a function of laser power. Our results show that the range of heating powers for producing heat shock response while avoiding damage in the mouse RPE is narrow. At powers of 64 and 70 mW, HSP70 immunostaining indicates 90 and 100% probability for clearly elevated HSP expression while the corresponding probability for damage is 20 and 33%, respectively. Tunel staining identified the apoptotic regions, and the estimated 50% damaging threshold probability for the heating (ED50) was ~72 mW. The staining with Bestrophin1 (BEST1) demonstrated RPE cell atrophy with the most intense powers. Consequently, fundus heating with a long-duration laser provides an approachable method to develop heat shock-based therapies for the RPE of retinal disease model mice.


2020 ◽  
Vol 40 (3) ◽  
pp. 766-782 ◽  
Author(s):  
Jennifer Bordenave ◽  
Ly Tu ◽  
Nihel Berrebeh ◽  
Raphaël Thuillet ◽  
Amélie Cumont ◽  
...  

Objective: Excessive accumulation of resident cells within the pulmonary vascular wall represents the hallmark feature of the remodeling occurring in pulmonary arterial hypertension (PAH). Furthermore, we have previously demonstrated that pulmonary arterioles are excessively covered by pericytes in PAH, but this process is not fully understood. The aim of our study was to investigate the dynamic contribution of pericytes in PAH vascular remodeling. Approach and Results: In this study, we performed in situ, in vivo, and in vitro experiments. We isolated primary cultures of human pericytes from controls and PAH lung specimens then performed functional studies (cell migration, proliferation, and differentiation). In addition, to follow up pericyte number and fate, a genetic fate-mapping approach was used with an NG2CreER;mT/mG transgenic mice in a model of pulmonary arteriole muscularization occurring during chronic hypoxia. We identified phenotypic and functional abnormalities of PAH pericytes in vitro, as they overexpress CXCR (C-X-C motif chemokine receptor)-7 and TGF (transforming growth factor)-βRII and, thereby, display a higher capacity to migrate, proliferate, and differentiate into smooth muscle-like cells than controls. In an in vivo model of chronic hypoxia, we found an early increase in pericyte number in a CXCL (C-X-C motif chemokine ligand)-12-dependent manner whereas later, from day 7, activation of the canonical TGF-β signaling pathway induces pericytes to differentiate into smooth muscle-like cells. Conclusions: Our findings reveal a pivotal role of pulmonary pericytes in PAH and identify CXCR-7 and TGF-βRII as 2 intrinsic abnormalities in these resident progenitor vascular cells that foster the onset and maintenance of PAH structural changes in blood lung vessels.


Blood ◽  
2011 ◽  
Vol 117 (17) ◽  
pp. 4511-4518 ◽  
Author(s):  
Katrina Soderquest ◽  
Nick Powell ◽  
Carmelo Luci ◽  
Nico van Rooijen ◽  
Andrés Hidalgo ◽  
...  

Abstract Natural killer (NK) cells play a major role in immunologic surveillance of cancer. Whether NK-cell subsets have specific roles during antitumor responses and what the signals are that drive their terminal maturation remain unclear. Using an in vivo model of tumor immunity, we show here that CD11bhiCD27low NK cells migrate to the tumor site to reject major histocompatibility complex class I negative tumors, a response that is severely impaired in Txb21−/− mice. The phenotypical analysis of Txb21-deficient mice shows that, in the absence of Txb21, NK-cell differentiation is arrested specifically at the CD11bhiCD27hi stage, resulting in the complete absence of terminally differentiated CD11bhiCD27low NK cells. Adoptive transfer experiments and radiation bone marrow chimera reveal that a Txb21+/+ environment rescues the CD11bhiCD27hi to CD11bhiCD27low transition of Txb21−/− NK cells. Furthermore, in vivo depletion of myeloid cells and in vitro coculture experiments demonstrate that spleen monocytes mediate the terminal differentiation of peripheral NK cells in a Txb21- and IL-15Rα–dependent manner. Together, these data reveal a novel, unrecognized role for Txb21 expression in monocytes in promoting NK-cell development and help appreciate how various NK-cell subsets are generated and participate in antitumor immunity.


1999 ◽  
Vol 77 (11) ◽  
pp. 886-895 ◽  
Author(s):  
Gordon Bolger ◽  
Jean-Claude Vigeant ◽  
Francine Liard ◽  
Bruno Simoneau ◽  
Diane Thibeault ◽  
...  

The human renin infused rat model (HRIRM) was used as an in vivo small-animal model for evaluating the efficacy of a collection of inhibitors of human renin. The intravenous infusion of recombinant human renin (2.4 µg·kg-1·min-1) in the ganglion-blocked, nephrectomized rat produced a mean blood pressor response of 47 ± 3 mmHg (1 mmHg = 133.3 Pa), which was reduced by captopril, enalkiren, and losartan in a dose-dependent manner following oral administration, with ED50 values of 0.3 ± 0.1, 2.5 ± 0.9, and 5.2 ± 1.6 mg/kg, respectively. A series of peptidomimetic P2-P3 butanediamide renin inhibitors inhibited purified recombinant human renin in vitro in a concentration-dependent manner, with IC50 values ranging from 0.4 to 20 nM at pH 6.0, with a higher range of IC50 values (0.8-80 nM) observed at pH 7.4. Following i.v. administration of renin inhibitors, the pressor response to infused human renin in the HRIRM was inhibited in a dose-dependent manner, with ED50 values ranging from 4 to 600 µg/kg. The in vivo inhibition of human renin following i.v. administration in the rat correlated significantly better with the in vitro inhibition of human renin at pH 7.4 (r = 0.8) compared with pH 6.0 (r = 0.5). Oral administration of renin inhibitors also resulted in a dose-dependent inhibition of the pressor response to infused human renin, with ED50 values ranging from 0.4 to 6.0 mg/kg and the identification of six renin inhibitors with an oral potency of <1 mg/kg. The ED50 of renin inhibitors for inhibition of angiotensin I formation in vivo was highly correlated (r = 0.9) with the ED50 for inhibition of the pressor response. These results demonstrate the high potency, dose dependence, and availability following oral administration of the butanediamide series of renin inhibitors.Key words: renin-angiotensin system, recombinant human renin, rat, renin inhibitors.


1977 ◽  
Vol 86 (4) ◽  
pp. 833-841 ◽  
Author(s):  
Ariel Gordin ◽  
Chester Meyers ◽  
Akira Arimura ◽  
David H. Coy ◽  
Andrew V. Schally

ABSTRACT An animal model for testing the in vivo potency of somatostatin analogs in inhibiting the release of insulin and glucagon is described. The secretion of these pancreatic hormones was stimulated in rat by infusion of arginine. The plasma insulin level increased almost to a maximum after an infusion of 10 min, while plasma glucagon rose more slowly, reaching its maximum only after a 30 min infusion. Concomitant infusion of graded doses of somatostatin (2.5, 10, 40 and 160 μg/100 g BW) for 30 min inhibited both insulin and glucagon release in a dose-dependent manner, enabling us to test somatostatin analogs for insulin and glucagon-suppressive activity in a semi-quantitative manner. Using this animal model, 3 analogs of somatostatin, [D-Cys14]-, [Ala2, D-Cys14]- and [D-Trp8, D-Cys14]somatostatin were tested in a 4-point assay. They all showed dissociated activity in inhibiting the secretion of glucagon more than that of insulin.


2018 ◽  
Vol 19 (9) ◽  
pp. 2695 ◽  
Author(s):  
Eun-A Kim ◽  
Yuling Ding ◽  
Hye-Won Yang ◽  
Soo-Jin Heo ◽  
Seung-Hong Lee

Marine-derived extract and/or bioactive compounds have attracted increasing demand due to their unique and potential uses as cures for various inflammation-based diseases. Several studies revealed anti-inflammatory candidates found in soft corals. However, the effects of soft corals on inflammation in an in vivo model remain to be determined. Therefore, the extract of soft coral Dendronephthya puetteri (DPE) was investigated for an in vivo anti-inflammatory effect in a lipopolysaccharide (LPS)-stimulated zebrafish model to determine its potential use as a natural anti-inflammatory agent. We also investigated whether DPE has toxic effects in a zebrafish model. No significant changes were observed in terms of survival, heart beat rate, or developmental abnormalities in the zebrafish embryos exposed to a concentration below 100 µg/mL of DPE. Treating the zebrafish model with LPS-treatment significantly increased the ROS, NO generation, and cell death. However, DPE inhibited this LPS-stimulated ROS, NO generation, and cell death in a dose-dependent manner. In addition, DPE significantly reduced the mRNA expression of both iNOS and COX-2 and markedly suppressed the expression levels of the proinflammatory cytokines, TNF-α and IL-6, in an LPS-stimulated zebrafish model. These findings demonstrate that DPE has profound anti-inflammatory effect in vivo, suggesting that DPE might be a strong natural anti-inflammatory agent.


2008 ◽  
Vol 19 (1) ◽  
pp. 198-206 ◽  
Author(s):  
Grzegorz T. Gurda ◽  
LiLi Guo ◽  
Sae-Hong Lee ◽  
Jeffery D. Molkentin ◽  
John A. Williams

Elevated endogenous cholecystokinin (CCK) release induced by protease inhibitors leads to pancreatic growth. This response has been shown to be mediated by the phosphatase calcineurin, but its downstream effectors are unknown. Here we examined activation of calcineurin-regulated nuclear factor of activated T-cells (NFATs) in isolated acinar cells, as well as in an in vivo model of pancreatic growth. Western blotting of endogenous NFATs and confocal imaging of NFATc1-GFP in pancreatic acini showed that CCK dose-dependently stimulated NFAT translocation from the cytoplasm to the nucleus within 0.5–1 h. This shift in localization correlated with CCK-induced activation of NFAT-driven luciferase reporter and was similar to that induced by a calcium ionophore and constitutively active calcineurin. The effect of CCK was dependent on calcineurin, as these changes were blocked by immunosuppressants FK506 and CsA and by overexpression of the endogenous protein inhibitor CAIN. Parallel NFAT activation took place in vivo. Pancreatic growth was accompanied by an increase in nuclear NFATs and subsequent elevation in expression of NFAT-luciferase in the pancreas, but not in organs unresponsive to CCK. The changes also required calcineurin, as they were blocked by FK506. We conclude that CCK activates NFATs in a calcineurin-dependent manner, both in vitro and in vivo.


Molecules ◽  
2018 ◽  
Vol 23 (8) ◽  
pp. 1892 ◽  
Author(s):  
Hanan Aati ◽  
Ali El-Gamal ◽  
Oliver Kayser ◽  
Atallah Ahmed

Extensive phytochemical analysis of different root fractions of Jatropha pelargoniifolia Courb. (Euphorbiaceae) has resulted in the isolation and identification of 22 secondary metabolites. 6-hydroxy-8-methoxycoumarin-7-O-β-d-glycopyranoside (15) and 2-hydroxymethyl N-methyltryptamine (18) were isolated and identified as new compounds along with the known diterpenoid (1, 3, 4, and 7), triterpenoid (2 and 6), flavonoid (5, 11, 13, 14, and 16), coumarinolignan (8–10), coumarin (15), pyrimidine (12), indole (17, 18), and tyramine-derived molecules (19–22). The anti-inflammatory, analgesic, and antipyretic activities were evaluated for fifteen of the adequately available isolated compounds (1–6, 8–11, 13, 14, 16, 21, and 22). Seven (4, 6, 10, 5, 13, 16, and 22) of the tested compounds showed a significant analgesic effect ranging from 40% to 80% at 10 mg/kg in two in vivo models. Compound 1 could also prove its analgesic property (67.21%) when it was evaluated on a third in vivo model at the same dose. The in vitro anti-inflammatory activity was also recorded where all compounds showed the ability to scavenge nitric oxide (NO) radical in a dose-dependent manner. However, eight compounds (1, 4, 5, 6, 10, 13, 16, and 22) out of the fifteen tested compounds exhibited considerable in vivo anti-inflammatory activity which reached 64.91% for compound 10 at a dose of 10 mg/kg. Moreover, the tested compounds exhibited an antipyretic effect in a yeast-induced hyperthermia in mice. The activity was found to be highly pronounced with compounds 1, 5, 6, 10, 13, and 16 which decreased the rectal temperature to about 37 °C after 2 h of the induced hyperthermia (~39 °C) at a dose of 10 mg/kg. This study could provide scientific evidence for the traditional use of J. pelargoniifolia as an anti-inflammatory, analgesic, and antipyretic.


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