Rutin-encapsulated chitosan nanoparticles targeted to the brain in the treatment of Cerebral Ischemia
Authors: Niyaz Ahmad
Atta Abbas Naqvi
Zeenat Iqbal
Md Aftab Alam
Mohammad Ashafaq
Mohd Samim
Rizwan Ahmad
Farhan Jalees Ahmad
Journal: International Journal of Biological Macromolecules (2016)
Discipline: BIOLOGY & BIOCHEMISTRY
Keywords: Brain pharmacokinetics and pharmacodynamics; Cerebral ischemia; Chitosan nanoparticles; Rutin; UPLC–MS/MS method validation.
Affiliations: Department of Pharmaceutics, College of Clinical Pharmacy, Dammam University, Dammam 31441, Saudi Arabia. Electronic address: ., Department of Natural Products and Alternative Medicine, College of Clinical Pharmacy, Dammam University, Dammam 31441, Saudi Arabia., Department of Pharmacy Practice, College of Clinical Pharmacy, University of Dammam, Dammam 31441, Saudi Arabia., Department of Pharmaceutics, School of Medical and Allied Sciences, Galgotias University, Gautam Budh Nagar, Greater Noida 201310, India., Neuroscience and Toxicology Unit, College of Pharmacy, Jazan University, Jazan, Saudi Arabia., Department of Chemistry, Faculty of Science, Hamdard University, New Delhi 110062, India., Nanomedicine Lab, Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, Hamdard Nagar, New Delhi 110062, India.

Abstract:  Objective: Rutin, a potent antioxidant, has been reported to reduce the risk of ischemic disease. Our study aims to prepare rutin-encapsulated-chitosan nanoparticles (RUT-CS-NPs) via ionic gelation method and determine its results, based on different parameters i.e. surface morphology characterization, in-vitro or ex-vivo release, dynamic light scattering and differential scanning calorimetry (DSC), for treating cerebral ischemia. Methods: UPLC-ESI-Q-TOF-MS/MS was used to evaluate the optimized RT-CS-NPs1 for brain-drug uptake as well as to follow-up the pharmacokinetics, bio-distrbution, brain-targeting efficiency and potential after intranasal administration (i.n.). Key findings: A particle size of &lt;100nm for the formulation, significantly affected by drug:CS ratio, and entrapment efficiency and loading capacity of 84.98%±4.18% and 39.48%±3.16%, respectively were observed for RUT. Pharmacokinetics, bio-distribution, brain-targeting efficiency (1443.48±39.39%) and brain drug-targeting potential (93.00±5.69%) showed enhanced bioavailability for RUT in brain as compared to intravenous administration. In addition; improved neurobehavioral activity, histopathology and reduced infarction volume effects were observed in middle cerebral artery occlusion (MCAO) induced cerebral ischemic rats model after i.n. administration of RUT-CS-NPs. Conclusion: A significant role of mucoadhesive-RT-CS-NPs1 as observed after high targeting potential and efficiency of the formulation prove; RUT-CS-NPs are more effectively accessed and target easily the brain. 

Retracted: No

PubPeer comments:
 Fig. 10.  Effect of Rutin loaded chitosan nanoparticles (10 mg kg) administration on hematoxylin and eosin staining in the brain sections of the sham, MCAO, and RUTCS-NPs + MCAO groups. (A) Cortical area of sham group animal showed uniform distribution of neurons. Normal neurons with the characteristic conical outlines with no abnormal features are seen. **(B) Tissues around infarcted area in the MCAO group show a focal area of vacuolation and neuronal loss.** (C) the RUT-CS-NPs + MCAO group rats show partial neuronal loss Repeated section of (B) is marked. ![file] (C) has some horizontal and vertical discontinuities in texture, emphasized here by adjusting the contrast, and then (at right) adding boxes as visual guides. ![file] , 
 #1 The mystery deepens when comparing with 10 *[below]* with *[above]* Fig 12 from [Ahmad et al (2017)] :  Synergistic effect of curcuminoids-CS-NPs administration on hematoxylin and eosin staining in the brain sections of the sham, MCAO, and MCAO u00fecurcuminoids-CS-NPs groups. (a) Cortical area of sham group animal showed uniform distribution of neurons. Normal neurons with the characteristic conical outlines with no abnormal features are seen. (b) Tissues around infarcted area in the MCAO group show a focal area of vacuolation and neuronal loss. (c) The MCAO u00fecurcuminoids-CS-NPs group rats show partial neuronal loss. ![file] 10A overlaps with 12(a), though not entirely, differing outside the marked zone. This is in addition to the duplicated areas in 12(c) and 10B. , 
 Below, Fig. 9(C):  Effect of Rutin pretreatment for 21 days on brain infarct size by TTC stain after middle cerebral artery occlusion for 2 h and reperfusion of 22 h. (C.) Representative photographs of brain sections stained with 0.1% TTC, and measurement of infarct volumes of MCAO, MCAO + RUT solution group, and MCAO + RUT-CS-NPs group are presented (C). Above, Figure 8A from [Ahmad et al (2017)] .  Effect of Safranal pretreatment for 21 days on brain infarct size by TTC stain after middle cerebral artery occlusion for 2u2009h and reperfusion of 22u2009h. A. Representative photographs of brain sections stained with 0.1% TTC, and measurement of infarct volumes of MCAO, MCAOu2009+u2009safranal mucoadhesive manoemulsion (SMNE) group, and MCAOu2009+u2009Mucoadhesive Nanoemulsion-Placebo group are presented . ![] I can see a rationale for re-using the same MCAO images in both papers. But  Sham from Fig 8 becomes  MCAO + RUT in Fig 9;  MCAO + SMNE from Fig 8 becomes  Sham in Fig 9 (after horizontal compression);  Sham+Placebo from Fig 8 becomes  MCAO + RUT-CS-NPs in Fig 9, apart from the white areas representing infarcts. , 
 Fig 2  Transmission Electron Microscopy (TEM) (B) images of Rutin loaded Chitosan Nanoparticles . Compared with *[right]* Fig 3(B) from [Ahmad et al (2020)] ,  transmission electron microscopy (TEM) [B] images of CS-coated-CH-loaded-PLGA-NPs . ![file] Same image, different materials. ,